History ThatOneAttack / RolePlayingGame

** The Elder Shroob Princess' last form in ''[[VideoGame/MarioAndLuigiPartnersInTime Partners in Time]]'' has an attack where her tentacle legs start spinning around her, forcing you to jump over them. It's not too difficult when she only has two legs, but when she has four legs, it's almost impossible to dodge. Couple that with the brothers flinching for a short time after getting hit so that once you get hit, it's impossible to ''stop'' getting hit, and you've got one incredibly annoying attack. Oh, and of ''course'' it does a ton of damage.

** Culex and his elemental crystals have nothing but stupid-powerful attacks (like the aforementioned Water Blast), but none of them compete with his one physical attack. He doesn't even move to attack you, all that happens is you instantly hear a slash and one of your characters takes about 150 damage at a respectable level (for comparison, all of your characters are barely below 200 HP, and most of the magic attacks will only deal 50-70 at that point). And because of its unpredictability, it's impossible to block unless you instantly press A as soon as it's his turn to move. Even when you [[GameBreaker put the Lazy Shell on the Princess]], which lets her take little to no damage from every attack in the fight, this attack will still deal about 50 to her. There's also his Dark Star special as well, which can pose a serious threat even to a Lazy-Shell-equipped Toadstool. At least it's only single-target.

** While several of the NintendoHard extra bosses have similar moves, the final three of Lenneth, the Ethereal Queen, and Freya are by far the worst. With Lenneth and the Queen, you at least have a slight chance of making it to the edge of the screen to dodge Nibelung Valesti and Celestial Star. Freya, however, will spam Ether Strike again and again without warning and cannot ever be disrupted. You only hope is certain stunning items which buy you a total of three seconds before she's back on the offense.

* In ''VideoGame/{{Mother 3}}'', [[spoiler:Porky]] has an attack that he, thankfully, rarely uses where he "coughs something up." It is the equivalent of using Offense Down AND Defense Down against your entire party '''3 TIMES,''' and can be dangerous if you don't have enough PP to raise your stats back up.
** From ''VideoGame/{{EarthBound|1994}}'', you have the Kraken's tornadoes. They do huge amounts of damage, hit everyone in the party, and can't be nullified or deflected like his other attacks can. Also, buffs won't help you; the Kraken's only nonoffensive attack neutralizes any buffs or debuffs you might have cast.
** Also, Diamond Dog's 'glorious light' attack. Anyone without certain equipment will most likely get paralyzed, killed, or confused. You're in trouble if you missed the Sea Pendant at the far end of the Lost Underworld.
** Also is the "spread some spores" attack that mushroomizes an ally, which causes both InterfaceScrew outside of combat and [[UnfriendlyFire randomly striking your own party]] or healing the opponent. It is uncurable in battle and can only be cured by visiting a healer: it's a huge pain when facing the ramblin' mushroom enemies, and an even bigger pain when this attack turns what should be an easy fight against Shrooom! into an aggravating LuckBasedMission.
** Made even worse when [[spoiler:Ness's Nightmare]] uses it. If Ness has a Night, Sea, or [[RandomDrop Star]] Pendant, it'll just waste a turn. If you gave that to a weaker party member, then you'll be up against an attack with a good chance of either being a one-shot kill, paralysis, or confusion. Against a DuelBoss, that's a very bad thing.
** The preferred attack of a few {{Metal Slime}}s from both games [[spoiler:(Criminal Caterpillar and Master Criminal Worm from ''VideoGame/{{EarthBound|1994}}'', and the Beanling and Black Beanling from ''VideoGame/{{Mother 3}}'')]] is a low-level PK Fire, which hits your entire party for massive damage the first time you can possibly fight them.

** The Clumsy Robot will waste most of its turns being clumsy. However, it can "fire a missile, making itself dizzy" for devastating damage, and eat a bologne sandwich to ''fully heal itself''. Both [[LuckBasedMission totally at random]]. [[spoiler:Actually, the sandwich is [[TheComputerIsALyingBastard a lie]] -- it makes the "HP recovery" noise and says "The Clumsy Robot's HP was maxed out", but it really does nothing at all. You'd need to hack the game to realize this, though.]]

** The Underground trial had several instances of annoying. The War Walkers had targeted abilities that grew in power depending on how many people surrounded the marked player. Don't notice and forget to run? Total wipe. And this part is an EscortMission. Thankfully, most groups left the NPC upstairs. What was even more annoying was the timed battle against the Avatar of Hamidon, which featured an automatic Confuse effect that required ''multiple'' applications of Status resist powers to avoid. If someone didn't notice the "confused" tag on their status bar, they could end up murdering the entire raid, or worse: HEALING THE BOSS.

** Ozruk in the Stonecore has ''three'' of these things. Elementium Bulwark which gives him a chance to reflect spells - on Heroic it becomes 100%. And on Heroic, he gets Paralyze - which isn't bad enough. But he follows it up with one of two things: Either Shatter or Ground Slam. Unfortunately? If you do not have a DamageOverTime effect on you (Which comes from Elementium Bulwark if you cast a magic spell at him, or meleeing him.) then you get hit with them. Also, Elementium Bulwark only reflects [[ExactWords Spells]]. Hunter's DamageOverTime ability does not count as a spell - and if you are playing an Arcane or a Frost Mage, better take out that fireball spell you never actually ''use''! What's worse is that Shatter and Gound Slam's ranges can be ''quite'' deceptive - Especially if [[RequiredSecondarySkills you were lagging just a bit]], since the game might not register you as more than 8 or 15 yards away.

** [[MeaningfulName Yaridovich]] and his [[KillItWithWater Water Blast]] has downed many a low-level run player.

** The [[WakeUpCallBoss Marid King]] has Freezing Sword, which he can use ''during your turn'' as a counter. It deals a decent chunk of damage which can be mitigated with an accessory that nullifies it, but even with that accessory you can still get Slowed by it, which makes the fight very irritating. The rest of his attacks are water-elemenntal, and there is no way to mitigate that at this point the game.

** [[spoiler:[[BonusBoss Dario]]'s]] attacks are all crazy powerful, but special mention goes to one in particular. If you use any kind of white element in the battle, he'll counter with [=ConductaRod=], a ''devastating'' black tech. [=Dash&Gash=] does way less damage than [=ConductaRod=], but does it enough to OneHitKill a non-black innate character.

** BonusBoss Darkeater Midir from the ''Ringed City'' DLC gets you coming ''and'' going. Sticking close to him in order to hit the head? Get an inch too far underneath and he'll use a downward fire breath attack, that covers a ridiculous amount of ground. Standing back to punish him with arrows or ranged lightning miracles? His Godzilla laser breath draws a line in the ground that deals massive damage...then he whips it around sideways, also dealing massive damage and moving insanely quickly, so you get disintegrated before you can do anything.

* ''VideoGame/EnchantedArms'' has bonus boss Omega and his Near Death Edge, which, true to its name, instantly chops the HP of anyone hit by it down to 1... and to rub salt in the wound, it also cancels any and all buffs and barriers on the victim, which makes the usual anti-boss tactic of setting up a 90% damage reduction via Raiga's Tiara Crusade more or less worthless. On the flip side, beating Omega allows you to recruit him... and he still has Near Death Edge, which works on [[GameBreaker absolutely anything in the game]]. Yes, including the final boss.

** [[EvilCounterpart Dark Lance]] is generally considered the toughest BonusBoss in ''IV'' due to one attack: Unload. In the player's hands, Unload is nothing special, since it's a physical attack on a mainly magical-attacking character, and it debuffs the user's attack afterwards to prevent it from being even remotely spammable. In the enemy's hands, though? Not only does Dark Lance have a sky-high physical attack, [[MyRulesAreNotYourRules Unload does ''nothing'' to his attack stat]] - he can, and ''will'', use it multiple rounds in a row. And it can hit multiple targets in a single action, [[TheComputerIsACheatingBastard which your version of Unload cannot do.]] Like your version, it hits 6 times, and if Dark Lance has previously buffed his Attack stat (and bear in mind that Dark Lance is ''resistant to dispel''), it can easily [=2HKO=] or even [[OneHitKill OHKO]] with just a single one of those shots.

** Almost ''every attack'' used by [[BonusBoss Dullahan]] counts as That One Attack. Dark Dawn might have been disappointingly easy, but Dullahan somehow got even harder.

** BonusBoss [[VideoGame/FinalFantasyVII Sephiroth's]] "Heartless Angel" attack, which drains all of your HP and MP in one shot. If you aren't able to interrupt it, you '''need''' the ability that lets you survive lethal blows with 1 HP (Most people assume it's a HPToOne attack because they haven't turned Second Chance off since they first got it ''way'' back in the beginning), but then you still have no MP to heal with. ''Ouch.'' Pray that you remembered to bring some Elixirs, and that you can use them fast enough before he finishes you off.

** ''VideoGame/KingdomHeartsBirthBySleep'' has the nameless [[BonusBoss optional boss]] [[RegionalBonus that the Japanese didn't get]]. This boss has Collision Magnet. Basically, the boss hauls you in with a rope and deals damage in mid air. First, it hurts. You need to be at a high level for this attack to not instantly bring you to your final Hit Point. Second, it's very fast and difficult to see coming, and unblockable. Third, it leaves you open for another attack, which can kill you if the rope managed to get you to one HP, without you being able to recover; even if you have Once More, because apparently the next attack, which you don't have enough time to recover for, counts as a separate combo. Your chance of victory is inversely proportional to how many times this boss decides to use this attack. This move was so bad that when the Japanese got their inevitable [[NoExportForYou Final Mix]], they nerfed this move to allow you enough time to dodge or heal, mainly to make the two ''new'' bonus bosses look challenging next to him.

** There's also BonusBoss ''Kurt Zisa'' from ''VideoGame/KingdomHeartsI'' and his infamous ''Silencega'' technique, which is able to completely lock your magic -- until you destroy the two crystal balls in his hands. His hard-hitting physicals make healing very important -- for which you have nothing but items, which can't be shortcutted in this game. [[GameOver Game Over]] is imminent.

** BonusBoss [[WesternAnimation/RunawayBrain Julius]] has a pretty big one too: he'll charge himself up with lightning, jump to the top of a tall building, then leap back down and bounce along the ground. It's really hard to avoid because of the AI's uncanny ability to know exactly where you're going to be when he jumps, so he usually ends up landing right on top of you. But that's not the worst thing about the attack. If he hits you, a random one of your commands will become greyed-out and have its reload rate slowed down so massively it's essentially taken out of the battle. Lord help you if he gets all your Curagas this way. Especially annoying is that, 9 times out of 10, the camera will lose your lock-on to Julius when he jumps, so you can easily get stomped simply because you lost track of where he was.

** Xemnas as he appears as a bonus boss in ''Kingdom Hearts: Final Mix'' has an attack where he replaces all of Sora's menu commands with "Shock", which harms Sora, and "Release", which ends the move. Thing is, "Release" hops randomly and rapidly through Sora's commands, making hitting it without missing the timing and getting Shocked very tricky. In addition: the attack continually drains Sora's HP either way until "Release" is selected, Sora can't use magic or items to heal himself during this time. Oh, and Xemnas is still attacking. The move is initiated by a very fast melee attack that has little-to-no telegraphing time.

** Yozora, the BonusBoss from the ''III'' DLC ''Re Mind'' has one attack where he is capable of stealing your items. This is very difficult to anticipate and it range from either your HP to recover himself, your Keyblade which leaves you completely incapable of attacking or blocking his attacks, or even worse the AutoRevive Kupo Coin where not only he robs you of a potential extra life but when you somehow brought him down, he'll use it to ''revive himself with half of his health bars along with another layer of armor HP''.

** BonusBoss The Yeti has "Crushing Blow", which does 999 damage (which is about five times the HP you'll probably have when you first confront him). The regular boss, Iron Golem, also has it, but doesn't have The Yeti's near-broken red mana gain, so if the Golem gets enough to cast, you were probably just a victim of bad luck.

* In ''VideoGame/ShadowHeartsFromTheNewWorld'' both the strongest BonusBoss and FinalBoss have a move called Lost Progress. True to its name, it's a StatusBuffDispel. The problem is that the bosses will use this ''instantly'' when you cast a StatusBuff - they just get a free turn as soon as you use a buff to cast Lost Progress. Because the developers thought that wasn't enough, the bosses then get ''another free turn'' immediately afterwards. You essentially ''cannot use buffs'' against these two bosses as a result.

** [[BonusBoss Culex]] and his elemental crystals have nothing but stupid-powerful attacks (like the aforementioned Water Blast), but none of them compete with his one physical attack. He doesn't even move to attack you, all that happens is you instantly hear a slash and one of your characters takes about 150 damage at a respectable level (for comparison, all of your characters are barely below 200 HP, and most of the magic attacks will only deal 50-70 at that point). And because of its unpredictability, it's impossible to block unless you instantly press A as soon as it's his turn to move. Even when you [[GameBreaker put the Lazy Shell on the Princess]], which lets her take little to no damage from every attack in the fight, this attack will still deal about 50 to her. There's also his Dark Star special as well, which can pose a serious threat even to a Lazy-Shell-equipped Toadstool. At least it's only single-target.

** [[BonusBoss Ragu O Ragla]]'s Volcanic Bomb in the first game, which deals 7000+ fire damage to all party members and is unsurvivable without absolutely insane amounts of grinding. The only other ways to withstand it is to make sure at least Cecilia is always equipped with a Goat Doll, or find Frog Badges, which nullify elemental damage.

** BonusBoss #367's Judgment Zero. In her first form it's barely worth mentioning, but in her second form it is practically guaranteed to do Overkill damage, which is an instant loss for you. Like Jihad, it is unblockable and non-elemental, so if she gets it off you ''will'' die. It's a lot more manageable in Blaze and Gloria, where it will only deal Overkill damage if Alanjame or Gariored is alone.

*** Another attack that is very similar are the Dragon's fire breath attacks where they fly out of attack range and do a lot of damage as well as Blaze. However [[spoiler:Avalanche Abaasy's is far worse then the other's. It also inflicts Paralysis and because of Avalanche Abaasy's huge 3,200 Ether power this does even more damage for the entire party if it connects]]. What will kill you in this fight is most likely the Blaze damage or the attack itself if you don't have a Level 10 Monado Armour which is almost needed for the [[BonusBoss Super bosses.]]

** In every game, Riku has an attack entitled Dark Aura, wherein he'll become invincible and fly in quick dashes at your character, before then slamming into the ground and sending out bursts across a wide area. It does heavy damage and is very hard to dodge. It's even more devastating in ''Chain of Memories'', although you do have 0 cards that can break it. It also helps that in Reverse/Rebirth [[GameBreaker you can use it yourself]] ''[[GameBreaker as]]'' [[GameBreaker Riku]]. Also, Ansem's ultimate attack in Riku's last battle with him will almost certainly be fatal unless you dodge it.

** There's also Titan Stamp from [[spoiler:Magestic Modred and Mischevious Naberius]]. This attack hits all of your party with a large radius and does a very large amount of damage having an Arts Multiplier of 4.0. Not only that but Monado Speed only works on one person and you won't likely have [[spoiler:Monado Armour]] by then which works on everyone.

** In every game, Riku has an attack entitled Dark Aura, wherein he'll become invincible and fly in quick dashes at your character, before then slamming into the ground and sending out bursts across the area. It does heavy damage and is very hard to dodge. It's even more devastating in ''Chain of Memories'', although you do have 0 cards that can break it. It also helps that in Reverse/Rebirth [[GameBreaker you can use it yourself]] ''[[GameBreaker as]]'' [[GameBreaker Riku]]. Also, Ansem's ultimate attack in Riku's last battle with him will almost certainly be fatal unless you dodge it.

** Mariah has an attack where she shocks you with a loose electric power line. It doesn't do that much damage, but inflicts stun. This wouldn't be so bad, except for two factors: First, you can only fight her with one character at a time, so if you get stunned, there's literally nothing you can do except wait a few turns for it to wear off (and hope she doesn't use the same attack again and stunlock you). Secondly, the event and battle against Mariah has an effective [[TimedMission time limit]], as you have to defeat/corner her before you are overwhelmed by her magnetic powers, so every second counts.
** Ultimate Clayman, the strongest bonus boss in the game, has an attack called "Fall Into Despair". It's an instant KO to your entire party, and there's absolutely no way to block, avoid, or survive it. Your only hope is to defeat her before she uses it, but that is heavily RNG-dependant. If you're masochistic enough to commit to taking her down, expect to die to this move at least dozens of times (assuming your party is strong enough to even last that long against her).

** Granted, it's otherwise an easy boss fight, and if you're constantly applying pressure, Darius will really never get a chance to use it, but God help you if you let Darius get off his super attack; he ''steals every party member except [[FragileSpeedster Therion]]'', (if Therion is dead when this happens, enjoy a TotalPartyKill instead) which is ''really bad'' because Darius attacks three times a round, more than enough to knock Therion on his ass. Mercifully, [[AntiFrustrationFeatures while Darius constantly swaps his weaknesses, he'll always retain a weakness for daggers, a weapon Therion will always have on him, and the party members are returned if he's broken.]] What's ''not'' so merciful is that Darius has access to Unconsciousness attacks; if Therion is alone, Unconscious, and Darius has more than 2 points remaining until he breaks, you've functionally already lost.
** Any [=AoE=] attack that has a chance to inflict Unconsciousness is this. Unconsciousness functions like Sleep, except the status doesn't wear off if your character is attacked. If your entire party is Unconscious, it's all but Game Over. Examples include Mattias' Black Thunder, Darius' Hellfire[[note]]Strangely, Lucia has the same attack, but it can't inflict Unconsciousness[[/note]], and Redeye's Bestial Roar[[note]]In fact, the last one is a bigger threat than Evil Eye, Redeye's Petrification skill, if only because Redeye can use the former from the start while the latter begins to be used after Redeye is down to 50% of its max HP[[/note]]. Better come prepared with a Conscious Stone!

** From VideoGame/EarthBound, you have the Kraken's tornadoes. They do huge amounts of damage, hit everyone in the party, and can't be nullified or deflected like his other attacks can. Also, buffs won't help you; the Kraken's only nonoffensive attack neutralizes any buffs or debuffs you might have cast.

** The preferred attack of a few {{Metal Slime}}s from both games [[spoiler:(Criminal Caterpillar and Master Criminal Worm from VideoGame/EarthBound, and the Beanling and Black Beanling from ''VideoGame/{{Mother 3}}'')]] is a low-level PK Fire, which hits your entire party for massive damage the first time you can possibly fight them.
** There are a lot of attacks in VideoGame/{{Mother 1}} that you will hate. Dehydration attacks, which lower your offense ''and'' defense at once, are nasty, as are last shot and PK Beam Gamma attacks which can instantly kill someone. Was it mentioned that you have to ''go back to town'' to revive a party member? And that the instant-kill attacks [[TotalPartyKill can be used by enemies]] ''before'' [[TotalPartyKill you get your second party member]]?

** [[BlowYouAway Xaldin's]] Wind Dragon in the ''VideoGame/KingdomHeartsII''. Multi-hit so it gets around Second Chance, does high damage, and is nigh-unavoidable. Thankfully, Reflega works perfectly well to shield you from it.

** The Data versions of the Organization battles in ''VideoGame/KingdomHeartsII [[UpdatedRerelease Final Mix+]]'' all follow a distinct formula, unlocking a very powerful attack (frequently called [[FanNickname desperation attacks]] by the fandom) once you damage them enough. The game will force you to deal with this, and sometimes will not let you defeat the boss until you have triumphed over this attack (Demyx's 'defeat 99 water clones in 30 seconds' and Luxord's 'Do you know the rules?' minigame are good examples: do what you like to their HP, but you won't win until you clear those challenges). If you're lucky, the boss in question will only use this desperation attack once (like Demyx and his final water clone challenge). If you're ''un''lucky, which you usually are, it will be added to the boss's pool of moves and reappear as often as the boss wishes. For example, Data Xemnas gets 'Can you spare a heart?', the move he used in the FinalBoss battle as a one-time scripted event/gameplay element (the one where he drains Sora's health and the player is forced to use Riku), as a desperation attack, that he can use as often as he pleases after his health dips below a certain point. The good news? Since it is no longer a scripted event but a regular attack, it can now be blocked by Reflect, or Limits (as Sora is invulnerable while executing a limit). The bad news? You had ''damn well better block it'', because Xemnas will drain Sora's health so fast this move might as well be a OneHitKill

** BonusBoss [[VideoGame/FinalFantasyVII Sephiroth's]] "Heartless Angel" attack, which drains all of your HP and MP in one shot. If you aren't able to interrupt it, you '''need''' the ability that lets you survive lethal blows with 1 HP (Most people assume it's a HPToOne attack because they haven't turned Second Chance off since they first got it ''way'' back in the beginning), but then you still have no MP to heal with. ''Ouch.'' Pray that you remember to bring some Elixirs, and that you can use them fast enough before he finishes you off.

** BonusBoss [[VideoGame/FinalFantasyVII Sephiroth's]] "Heartless Angel" attack, which drains all of your HP and MP in one shot. If you aren't able to interrupt it, you '''need''' the ability that lets you survive lethal blows with 1 HP (Most people assume it's a HPToOne attack because they haven't turned Second Chance off since they first got it ''way'' back in the beginning), but then you still have no MP to heal with. ''Ouch.''

* When you see the eponymous boss of ''VideoGame/DiabloII'' step back, ''run like hell'' because he's about to unleash [[http://www.infoceptor.net/strategy/diablo2/walkthrough/mission24/shot1.jpg a brutal stream of red lightning]] that can sap your health in seconds. This was nerfed in ''Lord of Destruction'', but it's still very damaging: it can still take most of your health in a single second, if not actually kill you. Diablo's ring of fire, his other attack, hits everything in every direction even when he's not on the screen, making it essentially unavoidable.
** There are various bugged monsters that can nearly instantly kill you. The hardest two are poison vipers, whose poison javelin is bugged and deals their regular attack damage 25 times per second on top of its poison damage; and gloams, who seem to deal 256 times their intended damage.
** The main thing that makes Nihlathak so dangerous is his Corpse Explosion, which works more or less exactly like the Necromancer's in that it deals out a percentage of the dead monster's attack as damage, half-fire, half-physical. If you thought the spell was good in your hands when brought against armies of mooks, it's even more harmful when you're the target and the game's infamous HealthDamageAsymmetry is ''not'' on your side. In the game's max difficulty the damage is nerfed to a fifth of what it should be and it ''still'' tends to pack enough of a punch to OneHitKill well-built characters.

* ''VideoGame/{{Drakengard}}'':
** When fighting Furiae, there's an attack where she sends a dozen swords at you. And you have to dodge every single one, or you take full damage. It is avoidable, if you use homing fire, or the dragon's fully-powered LimitBreak, but [[GuideDangIt you probably wouldn't know that on your first try]].
** Manah in the canon ending is a pain in the butt. She has this annoying attack in the middle of the fight where she summons rings that come from her abdomen, not too bad. However, after [[TurnsRed taking so much health from her]], she decides to summon the rings from all angles... Have fun dodging those.

* Thresher maws in ''VideoGame/MassEffect1'' continually burrow into the ground and reappear somewhere else. That "somewhere else" can be ''directly under you.'' Instant game over. That isn't even getting into its ''actual'' attack, spitting out acid which completely ignores your shields and take off more than half of the [[CoolTank Mako's]] hit points (if you're fighting on foot, the acid attack is very likely to insta-kill). The general strategy people recommend for thresher maws is "run the hell away."
** Biotic enemies love to spam an ability that knocks Shepard down, leaving him/her completely helpless. Fighting against multiple biotics means that you can be stuck to the floor for quite a while, watching your health whittle away without being able to do anything about it (even ''pause the game'').
** The rocket drones in the Luna base frequently fire extremely powerful rockets. They're almost guaranteed to be a OneHitKill unless you have high-level Immunity or very high shields.
* In ''VideoGame/MassEffect2'' there are a ''lot'' more examples of this trope. There are the [[DemonicSpiders Scions]], whose Shockwaves tear your shields to pieces and ignore cover. There are the [[ThatOneBoss Praetorians]], whose Death Choir attack decimates anyone within blast range and fully recharges their Barrier. There's the Oculi, whose energy beams stagger you and deal massive damage. There's [[PeoplePuppets Harbinger himself]], who's fond of using a Singularity attack that knocks you out of cover so he can bombard you with Warp blasts.
* In ''VideoGame/MassEffect3'', Banshees have a homing Warp attack that inflicts lingering damage, a Nova-like attack that strips shields but is unlikely to kill, and a claw swipe. These are all annoying, but manageable. They also have a OneHitKill [[ImpaledWithExtremePrejudice melee attack]], coupled with a [[TeleportSpam generous]] definition of "melee." Other enemies, like Phantoms, Brutes, and Atlas mechs, have instant-kill attacks, but they can only use theirs as a follow-up to a regular melee attack, while the Banshee can grab you the moment you enter its InstantDeathRadius.

* ''VideoGame/NeverwinterNights'' has Harm. A ''very'' distinct pillar of red light slamming down upon you and reducing you to 1 HP. If you have other enemies nearby or are in some kind of damaging effect, prepare to die.
* ''VideoGame/MegaManStarForce'':
** Apollo Flame in the second and third game has an attack where he drops a miniature sun on Mega Man's side of the field. This attack comes out very quickly, it can't be dodged or blocked (unless you knock him out of it first), and it cracks your panels. It also hits multiple times, so not even a Barrier can save you.
** Sirius, from the third game, has Satellite Blazer, which hits and ''breaks'' every tile of the field and can't be blocked (or dodged for that matter, unless you have Air Shoes). He also has a move where he detaches his wings and starts [[BeamSpam blasting the field with elemental lasers]] -- it can't be blocked, and can easily knock you out of an elemental Noise form if you're not careful.
* ''VideoGame/MinecraftDungeons'': [[spoiler:The laser attack from Heart of Ender. This attack can instantly kill you within less than 5 seconds if you don't avoid it properly, and even touching it for a little bit can take half of your health. Unfortunately, the boss also spams fire all over the place, making completely avoiding it near impossible. Luckily, the laser can be blocked through the Totem of Shielding.]]
* The final boss of ''VideoGame/SkiesOfArcadia'' brings us the Silver Nightmare attack, where he possesses one of your party members and forces them to use one of their special moves against one of their own allies. It has priority over EVERYTHING, even defensive moves like Justice Shield, and is the only damaging move in the game that has this high a priority. And the possessed party member loses their action for that turn, and quite often you will see him turning Vyse's Pirates' Wrath into a OneHitKill of your SquishyWizard, making that two actions in one turn you just lost, and often more because you get to watch your characters uselessly start using their shield moves. Have fun catching back up with the battle flow!
** As far as ship battles are concerned, there's Bluheim's Blue Winds attack. While technically by itself it does the least damage out of Bluheim's attacks, it causes the ''entire next round'' to be filled with nothing but tiles giving an advantage to Bluheim, which is just as painful as it sounds. The only other attack in the game that does this (Auriga's Hull Ram) is easily avoidable by casting Quika; the best you can do with Blue Winds is use the Guard command...in which case the next round is instead filled with tiles that give Blueheim ''slightly less'' of an advantage.
* Flash game ''VideoGame/{{Sonny}}'' has Baron Brixius' Tick Tock debuff, which deals damage equal to 10% of the victim's maximum HP... and continues to do this for 10 turns. It also cuts any healing they receive in half, can be cast on multiple characters at once, and can't be removed by status-removing spells. Note that this game has no multi-target healing and no way to revive dead allies. Note also that Baron Brixius would be a MarathonBoss ''without'' this attack. With it, he becomes ThatOneBoss. The only saving grace is he likes to use it on ''himself'' if you last long enough.
* The ''VideoGame/EtrianOdyssey'' games are liberally sprinkled with these, as you'd expect from a game this NintendoHard. In general, almost no enemy's basic attack will seriously endanger anyone so long as you have a healer, but even common enemies have abilities such as giving the entire party status effects or doing enough damage to one-or-two shot even the hardiest Protector. The fact that StatusEffects can entirely ''prevent'' these moves from being performed is what keeps them from being {{Useless Useful Spell}}s.
** Shin fron ''The Drowned City'' has a nasty one called 'Demon's Kiss'. It hits various random party members multiple (from two to ''nine'') times, for various amounts of damage, and then heals the boss.
** Enemy {{Combination Attack}}s (signaled by the text "(enemy) stands ready!") can be stopped by killing or disabling the enemy who will perform the attack, but failure to do so and they will do something seriously nasty to your party, such as status effects to all units or just killing at least half of them with massive damage.

* ''VideoGame/EpicBattleFantasy''
** In ''Epic Battle Fantasy III'', there's Doomsday, used by [[BossInMookClothing Cosmic Monolith]]. It deals huge dark-elemental damage to everything on the field - but Cosmic Monolith actually absorbs dark, meaning it can bring your whole party to near death while healing itself. The attack is used every three turns, so if you can't outdamage the healing (taking into account that you also have to recover your health in meantime), you're screwed. An optional fight with two Cosmic Monoliths is actually harder than the FinalBoss.
** ''Epic Battle Fantasy 4'' has a few, but one of the worst is used by the Clay Idols (which are otherwise a pushover mook). They have an attack that drains a character's MP. What makes it so nasty is that the amount it drains is completely ridiculous; a single hit can steal roughly 90% of a character's MP total, essentially forcing that character into backup so that their MP can (slowly) regenerate and making them practically useless for the rest of the battle, or else forcing you to run away and restore your MP out of battle. For this reason, it's generally recommended to take out Clay Idols on sight, before even buffing (which you would normally spend most of the first turn doing).
** [[EvilCounterpart Dark Lance]] is generally considered the toughest BonusBoss in ''IV'' due to one attack: Unload. In the player's hands, Unload is nothing special, since it's a physical attack on a mainly magical-attacking character, and it debuffs the user's attack afterwards to prevent it from being even remotely spammable. In the enemy's hands, though? Not only does Dark Lance have a sky-high physical attack, [[MyRulesAreNotYourRules Unload does ''nothing'' to his attack stat]] - he can, and ''will'', use it multiple rounds in a row. And it can hit multiple targets in a single action, [[TheComputerIsACheatingBastard which your version of Unload cannot do.]] Like your version, it hits 6 times, and if Dark Lance has previously buffed his Attack stat (and bear in mind that Dark Lance is ''resistant to dispel''), it can easily [=2HKO=] or even [[OneHitKill OHKO]] with just a single one of those shots.
* ''VideoGame/DarkSouls'' has quite a few. Chaos Witch Quelaag has a devastating area of effect explosion attack; even with high fire resistance, it's likely to stagger you and take off quite a chunk of health. It's telegraphed well in advance[[note]]When Quelaag hugs the spider, ''run''[[/note]], but if you don't get your shield up or get away, you'll get your face blasted off.
** Grappling attacks are unblockable and will usually take off at least three quarters of your health bar every time you're grabbed. Sure, they're telegraphed, but if you're focusing on finishing off another monster or overestimate your dodging ability, it's very easy to get an amateur tracheotomy courtesy of an Infested Ghoul's teeth, or pecked to death by a Crow Demon, or chewed on by the Gaping Dragon, [[TheManyDeathsOfYou or stabbed through the chest by a Wailing Ghost, or smashed into the ground by the Iron Golem]]...
** The Basilisk's attack, which spews a gray cloud of fog that causes curse. Curse is easily the deadliest status ailment in the game, and extremely hard to remove.
** The basic Hollow, the weakest enemy in the game, has an attack where it frantically swings its weapon while dashing forward. Normally even this attack isn't all that strong... unless that Hollow happens to be holding a torch instead of a broken sword, in which case the attack can break pretty much any amount of [[ImmuneToFlinching Poise]] and evaporate your health bar as you are helplessly stunlocked.
* ''VideoGame/DarkSoulsIII'' is no slouch in this department either.
** Holy Knight Hodrick's ripostes. When Hodrick invades you, he's a faintly absurd parry god who can block your attack, then one-shot you with a riposte to the face.
** Aldrich, Devourer of Gods, has [[spoiler:Gwyndolin's]] magic arrow bombardment. In his first phase, it draws a straight line that is fairly easy to avoid. In his second, it ''hunts you down'', can stunlock you to death, and lasts for fifteen seconds, which, in the heat of battle, can feel like a week - especially since he doesn't have to do anything to sustain it once it's going, and thus can cast more spells or hit you in the face.
** The King of the Storm/Nameless King fight is just plain annoying, but the blast attacks are the worst thing about its first phase: the downwards fire breath creates a spreading, fast-growing pulse of fire about the size of Kansas, while the lightning spear shockwave is a devastating blast that's hard to dodge accurately.
** The Consumed King's charge has a messy hitbox and a wind-up time that is only perceptible to mayflies.
** In the Twin Princes fight, there's Lorian's teleporting dive attack, which has a wind-up of about a nanosecond. Overextend even a little and he blinks out of existence, then reappears right above you and slams his sword into the top of your head.
** The FinalBoss has a bunch of fun attacks. In his first phase, he has some very powerful spells in his sorcery mode, including the ability to put up a proximity-activated soulmass ''while'' firing a WaveMotionGun that will disintegrate you if you get caught in the blast. In his second, he has a devastating multi-hit combo that's then followed up with a hugely powerful AOE. Get caught by the first and the second will vaporise you.
** Sword-wielding Ringed Knights have a five-hit sequence that is almost impossible to interrupt. When you see one's sword catch fire, either beat him down before he starts the attack, or ''get away''.
** Judicator Giants can summon multiple annoying ghosts to attack you, but if the Ruin archers are turning up, ''hide behind something''. They put out agonising volleys of staggered shots that can stunlock you into oblivion.
** BonusBoss Darkeater Midir from the ''Ringed City'' DLC gets you coming ''and'' going. Sticking close to him in order to hit the head? Get an inch too far underneath and he'll use a downward fire breath attack, that covers a ridiculous amount of ground. Standing back to punish him with arrows or ranged lightning miracles? His Godzilla laser breath draws a line in the ground that deals massive damage...then he whips it around sideways, also dealing massive damage and moving insanely quickly, so you get disintegrated before you can do anything.
* The Procrastination Giant in ''VideoGame/KingdomOfLoathing'' will sometimes counter melee attacks by sneezing on you. This causes the status effect "Cunctitus", which makes you procrastinate. Which is to say, a good 80% of the time you try to make a move in combat, you get the message "You decide to [perform this action] later." This is usually followed by the message, "You lose."
** The Protagonist from the preceding area ([[Franchise/FinalFantasy Penultimate Fantasy Airship]]) can cause the [[LaserGuidedAmnesia "Temporary Amnesia"]] effect, which disables ''all'' your skills. Mildly annoying if you're a Muscle or Moxie class which can just spam their default attack to win, deadly if you're a [[SquishyWizard Mysticality class]] who relies on spells to fight.
** To fully qualify, those (along with a high chance of getting poisoned in multiple ways from multiple sources during the next major quest) are the most memorable attacks any non-boss will use against a brand new player, and are nastier than any boss attack up to that point as well. They fit this page because ''every'' player at some point was a brand new player and very few will have been ready with appropriate counters to all of those. The game universe as a whole features numerous examples of devastating and truly unfair enemy attacks, but the nature of the game is such that experienced players usually have so many effective fighting styles and metaphorical "I win buttons" ready that it's hard to single anything out as a threat to ''everyone''.
* ''Franchise/TheElderScrolls'':
** ''[[VideoGame/TheElderScrollsIIIMorrowind Morrowind]]'': Greater Bonewalkers have an ''infuriating'' "damage attribute" spell. Note that says "damage" and not "drain." "Drained" attributes will go back to normal once the spell wears off. "Damaged" attributes will stick with you until you heal them with a temple blessing or potion. It's incredibly frustrating to encounter a greater bonewalker halfway through a difficult dungeon only to have him damage your strength attribute so much that you are forced to dump half your inventory (strength determines how much you can carry) in order to flee back to civilization to heal.
** ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'': High level draugr are capable of using the same dragon shouts as you, including the "Disarm" shout. Any weapon you are holding will fly out of your hand and across the room. This alone is annoying, but reasonable. It becomes unreasonable when your weapon occasionally flies into unreachable places, such as ''through the floor or wall.''
* Terracor's curl, the possession attack of the two Shade bosses (which, in addition, can potentially kill any possessed party member so the bosses can recover part of its energy) and Mystic Spider's swallowing attack in ''VideoGame/TheLastStory''.
* PSI Bitchkill in ''VideoGame/TheHalloweenHack'', which can kill your entire party in one hit. Thankfully, it can be reflected.
* Hit-all attacks in ''VideoGame/TheDenpaMen'' are oftentimes devastating, but among the most dangerous is the "Extended its roots" attack utilized by a great number of plant-like enemies. It smashes the entire party for a large amount of Earth-type damage. Even orange, Earth-type Denpa Men and bulky tanks will probably be left with little health after just one, and you can almost assuredly kiss your ability-users goodbye when it hits. The [[BossInMookClothing Hydraplants]] can attack ''twice'' with it in one turn, almost assuredly leading to a TotalPartyKill.
* In ''VideoGame/LilMonster'', the Meteor Drive attack is the most powerful attack in the game, and the player cannot obtain it until right before the FinalBoss. But even early-level enemies, and those in the earlier tournaments, can use it. Even when used by the weakest monster in the game, it still does over 100 damage.
* [[spoiler:Demon Lord]] Trevor in ''VideoGame/ExitFate'' has Annihilation Ray, which does a fixed 5000 damage to a character. That is much more HP than any of your characters can realistically have, and it can't be weakened with Shield. A later boss, Mephisto, brings it back and it's just as devastating.
* ''VideoGame/LufiaAndTheFortressOfDoom'':
** The game has archer enemies that come in groups of three to four and love to spam Hi Arrows, an attack item that hits everyone in your party for rather hefty damage. An entire group of archers using Hi Arrows will easily knock out Lufia and leave the Hero and Aguro on the verge of falling.
** The final bosses, Daos and [[spoiler:Guard Daos]], have Amnesia and Figual. Both have a high chance of inflicting paralysis or confusion respectively on your entire party. Amnesia is far more dangerous on its own, but because [[spoiler:Guard Daos]]'s moveset was reduced to two attacks in the western releases, Figual gets spammed non-stop during the final fight.
* ''VideoGame/LufiaIIRiseOfTheSinistrals'':
** The game has Mortal Blow, which has a high chance of instant death. What makes it That One Attack is that the enemies that use it, the Ninja and [[BlindIdiotTranslation Asashin]], are ''insanely'' fast both out-of and in-battle, meaning it's very difficult to avoid.
** The Gold Dragons near the end of the [[BonusDungeon Ancient Cave]] attack ''three times per turn''. One of their attacks is Stardust Blow, an extremely powerful [=fire/holy=] attack that hits everyone in the party. If a Gold Dragon uses Stardust Blow twice? Everyone in your party is dead, with the possible exception of [[SuperToughness Dekar]]. Uses Stardust Blow three times, or ends with [[HolyHandGrenade Fry]]? Nothing's going to save you then.
* ''VideoGame/LufiaTheLegendReturns'':
** Spiritual Force of Chaos, Amon's signature attack which can inflict confusion on every party member. Normally, only three members (of up to nine) can attack per turn. Confused members aren't under this restriction. [[spoiler:Oh, and Guard Daos has this attack too.]]
** There's also Destroy, the multi-target instant-death spell. Under normal circumstances, it ''might'' knock off one or two members (and fallen members revive after battle anyway). But after [[spoiler:the party gets drugged by Leydeck]], you're reduced to ''two'' members, at which point Destroy becomes horrifyingly likely to cause a TotalPartyKill.
* Reaper Hit in ''VideoGame/LufiaTheRuinsOfLore'', an attack with a chance of instant death. That is only encountered in the BonusDungeon. That ''only the main character'' can enter (with his {{Mon}}, but WeCannotGoOnWithoutYou applies to human party members).
* ''VideoGame/LufiaCurseOfTheSinistrals'':
** Both forms of [[spoiler:Gades]] have a three-hit combo attack that knocks you down on the first hit, leaving you vulnerable to the rest of the combo. The first form's combo will cleave off more than half of your HP meter with one combo. The second form's combo can kill [[GlassCannon Tia]] from full HP easily.
** The scarecrow enemies' sleep spell. Getting hit by it is nigh-guaranteed sleep, which leaves the character completely immobile and unable to swap out until it wears off or you cure it...perfect for the scarecrows' highly-damaging fireball attack. In the first dungeon you encounter them in, Maxim and Tia ''will'' get killed if they get hit by sleep without anything on hand to cure them.
** The spinning top enemies aren't too tough, and even their spinning attack that stunlocks your character won't do much damage with a bit of buffing. The red variants you encounter in the Ancient Cave do around '''200''' damage a hit even with high DEF, guaranteeing knock-out if you get hit by their spinning attack.
* If you're taking the bad ending path in ''VideoGame/{{Undertale}}'', you'll have to fight [[spoiler:Sans]] at the very end, and his ''opening attack'' is this. If you actually survive it, he'll lampshade it, stating that he had wondered why people don't just use their strongest attack first. And if you have to repeat that battle, they'll sometimes interrupt his own intro speech with the attack, to catch you off guard even if you've memorized the pattern. They also get an attack that is mechanically a copy of the difficult hoverbike sequences from ''VideoGame/{{Battletoads}}''. Finally, there's the last attack: in addition to being significantly faster and more hectic than their opening move, it lasts for a full ''30 seconds''.
* ''VideoGame/LastScenario'':
** The [[WakeUpCallBoss Marid King]] has Freezing Sword, which he can use ''during your turn'' as a counter. It deals a decent chunk of damage which can be mitigated with an accessory that nullifies it, but even with that accessory you can still get Slowed by it, which makes the fight very irritating. The rest of his attacks are water-elemenntal, and there is no way to mitigate that at this point the game.
** Castor has ''Maelstrom'', a single-target attack that deals damage and inflicts slow, berserk, chaos (akin to confusion in other [=RPGs=]) and petrification. If you don't have a way to block at least one of these effects, you'll be spending more of your time recovering from Maelstrom than actually fighting Castor as he pounds you into the floor over and over again.
** [[spoiler:Alexander]] has ''Lionheart'', which deals ludicrously high damage and ''hits twice''. Even if you're somehow able to tank the first hit, the second one will finish off even [[MightyGlacier Matilda]], or if the first hit was enough, it ''targets a second party member''. Basically, unless you've been using lots of Vitality Capsules to jack up your party's defense, it constitutes half of a TotalPartyKill.
* ''VideoGame/TheWorldEndsWithYou'':
** Yodai Higashizawa, the first game's Game Master [[spoiler:(of the first week, that is)]] has his electric orb spam, announced with "I'll char your bones black!" This is his only attack that targets ''both'' Shiki and Neku simultaneously, requiring them to stop attacking entirely and focus exclusively on defense until it's over.
** ''[[VideoGame/NEOTheWorldEndsWithYou NEO]]'' has [[spoiler:Ayano Kamachi]]'s slap attack. One by one, she stuns your party members (most of them -- she doesn't do it to Rindo or [[spoiler:Shoka]]) before walking up to them and delivering an ''extremely'' powerful slap that can drain all your HP if they all connect. It's possible to free your party members by breaking the chains she summons, but if you don't have powerful ranged pins (or if you do but they're on the targets for this attack) you won't make it in time. Even worse, she only uses it at low health ''and'' gets a LastChanceHitPoint that guarantees she's able to do this move, and having to redo the entire fight due to this attack can be very frustrating.
* ''Videogame/SaltAndSanctuary'':
** The Bloodless Prince, a gigantic three-faced golem, is actually relatively easy as long as you stay up close, due to massive telegraphing of his attacks despite their area of effect. Again, if you stay up close. If you don't, the Prince will decide to close the distance by way of flopping onto you from afar, which causes a massive quake that, due to ridiculous, arena-encompassing area of effect, is essentially impossible to properly dodge unless you're at the very edge of the arena.
** The Witch of the Lake, ThatOneBoss extraordinaire, has her infamous "flame machinegun" that sprays ridiculous amounts of fire from her staff into an area in front of her. The only way to avoid this attack is to either be far away so only a few bits reach you, or to be right under her so the fire goes past your head. If you're at medium distance, and don't have an excellent shield up ''that exact second'' you are dead, no questions asked. While her other attacks are horribly damaging you can at least survive them with some last-second dodging, but if you're in the impact zone for this one not even the best roll timing will save you.
** [[spoiler: The Forgotten King, from the Three]], has an untelegraphed and very quick kick that looks more like he's simply stepping on you casually. It's close to impossible to react on time so the only way to avoid it is to be dodging before it starts. It does little damage, but it ''will'' knock you down, which is not a good thing when you're facing three bosses at once (as is this particular fight's case).
* ''VideoGame/JojosBizarreAdventureThe7thStandUser'':
** Several bosses, including the Water Claw and (in the BossRush) Hanged Man can "go for the jugular", which doesn't do much damage but has a very high chance of causing instant death. This is a serious problem in a game where you're limited to two party members for the vast majority of fights, including these two. Tower of Grey (the ''very first boss'') gets a more accurate version of this named Tower Needle, though he doesn't use it in the first fight unless you're on Hard Mode.
** All of the Anubis fights have "I've memorized it!", a stacking general buff. They combine this with Iai Slash, a very strong party attack that just gets even stronger as the fight drags on. Whether you're able to win these fights at all is dependent on how quickly you're able to buff your party before they get too powerful.
* In ''VideoGame/BetrayalAtKrondor'', the spell "Grief of 1000 Nights" freezes a character for a number of rounds. This is nice when used by one of your mages; however, if enemy mages use it on your party it is far deadlier, as when all of your characters are frozen the game treats it as a Game Over, even if their hit points are still high enough to survive more attacks before the spell wears off. It gets worse in combats with multiple enemy mages, especially if your party screws up a surprise attack and goes last, as sometimes you'll get frozen up so quickly you may not even get a turn.
* ''VideoGame/ArmoryAndMachine'':
** This trope is invoked with the various rat enemies and Rat King boss in the Badlands, the second area of the game. All of them have rather weak basic attacks, and they also have one attack that has a slower cast time but deals a ''whopping'' 300 or 400 HP damage at a point where you have 600 max HP ("Bite" for the Sad Rats and Mad Rats, "Gnaw" for the Dust Crawlers, "Radioactive Bite" for the Glowing Rats, and "Royal Decree" for the Rat King), pretty much guaranteeing a defeat if it hits you. The trick here is to use the Stun ability, which causes their prepared attack to fail and do nothing. Out of the four, the Dust Crawler's Gnaw is especially bad, as it has a much shorter casting/interruption time than the rest of the enemies' dangerous moves.
** The Vacuous Bats in the Cliffs area will usually use a move called "Fly", which does nothing. However, their AIRoulette will randomly use "Swift Bite", which deals 300 damage to your 600 HP when you first encounter them. If they use this twice before you can beat them, you're toast. You can use Stun to stop it, but that takes up a precious skill slot and will hamper your potential DPS.
** The Ninja Frogs in the Cliffs are similar to the bats, using several fake-out moves that do nothing, but after their AIRoulette uses "It's Coming", it has a high chance to use "Shuriken" to deal 300 damage, and unlike Swift Bite Shuriken has a far shorter casting time making it harder to anticipate and interrupt. The only good news is that sometimes it might user Honorable Healing instead of Shuriken, which heals you for 100.
** "Chip Swarm" by the Pebble Swarm. It hits for [[DeathOfAThousandCuts very weak damage but is used extremely rapidly]], which will immediately interrupt any of your more powerful attacks that have a cast time, and this also means that it cannot be interrupted since you can only disrupt one of the hits. Furthermore, this attack can last for a huge period of time, eating away at your shields and health. The Rock Golem boss also uses a similar move, but it doesn't last as long as the Pebble Swarm's.
** Of all [[spoiler:the [[FinalBoss Original Machine's]]]] attacks, we have "Target Laser". Its other attacks hit harder at 1000+ damage or so but can be interrupted in the cast period to prevent damage entirely. Target Laser deals only 250 damage but the boss [[SpamAttack uses it 7 times in a row]] followed by an 80 damage shot. This would normally seem easy to chain-interrupt as Target Laser's first cast starts slow, but each subsequent casting time is lowered regardless of cast success. You only have four moves that can reliably interrupt them, and they take 10-20 seconds cooldown. This means that unlike all its other moves, you will not be able to interrupt all of it and will take at least 1-3 hits plus another 80 damage at the end.
* ''VideoGame/ArmoryAndMachine2'':
** The Snake and the [=JrBot=] have "Paralyze", which permanently stuns you until they kill you with their attacks. The good news is that it has a long charge time to interrupt and is a great opportunity for you to use Bomb on them. The Wild Snake's version of Paralyze fortunately only stuns you for 8 seconds, but it's still a good way for it to deal heavy damage on you.
** "Crab Toxin" and "Poison", used by the Giant Crabs and Toxic Slimes respectively in the Wilderness. Unlike the regular Crab's Crab Poison which merely lowers the damage of your next attack by 5, these two inflict an ''actual'' poison status that lasts 30 seconds and lingers even after the battle ends, halves all your damage dealt, and deals 2 damage to you every few seconds which will interrupt your casting time attacks. Players who assume that they can simply take this Poison as lightly as Crab Poison will be in for a ''very'' rude awakening.
** The Zombie's "Bite". It isn't a very painful move but the Zombie can spam it if the AIRoulette chooses to, and if the attack connects (due to overwhelming your interruption move cooldowns) it will heal the Zombie for 50 of its already-high 200 HP, effectively wasting 1/4 of your efforts in killing it.
** The Forest Nymph's "Protect". It has an extremely fast cast time, tends to be used almost every alternate turn, and if not interrupted it will provide a damage shield to the Nymph. Said damage shield makes them regenerate health from Blast- and Explosion- type moves (pretty much your entire arsenal for the first 4 areas of the game) and lasts 10 long seconds, meaning that if they manage to pull this off ''once'', you're as good as dead if you lack any physical or elemental attacks.
** The Angry Orc and the Sleepy Guardian Orc have "Club Smash", which deals a huge 40 damage where you have only 100 max HP. It's the first long-casting attack in both games that ''[[ImmuneToFlinching cannot be interrupted]]''. This enforces you to have both a healing move and a way to increase your dodge or defense, and if it's used multiple times in succession to overrun your Regen use, you're out of luck. It's one of the reasons why the Sleepy Guardian Orc is the [[ThatOneBoss toughest of the five bosses in the Wilderness]].
* ''VideoGame/GranblueFantasy'', having as many raid bosses as it does, has its fair share of these.
** Colossus Omega's Dimensional Cleave, which has a damage output so high that not even Phalanx III is strong enough to stop its target from getting killed, even if you're using a Water team. This attack is what makes this raid a WakeUpCallBoss for some newer players, as mitigating it can be a challenge.
** Conjunction, used by both versions of Grand Order. It's a party-wide HPToOne attack, and on the easier version of the raid, it also ''randomizes the cooldown length'' of all your skills. If it happens to shut you out of your healing skills for several turns... well, hopefully you have a spare Full Elixir to get back into the fight.
** Proto Bahamut (both the regular and Impossible versions) has Skyfall, which deals [[FixedDamageAttack ten million]] dark damage to the entire party. This ''will'' kill you unless you're able to get a full damage cut for the party. And the regular version is guaranteed to use it twice during the fight.
** While the Impossible version of Proto Bahamut isn't guaranteed to use Skyfall, it ''is'' guaranteed to use the way nastier Supernova, which deals 95% of each party member's maximum HP as [[NonElemental plain damage]]. While it does less damage than Skyfall, it is ''much'' harder to guard against, as plain damage ignores most defensive buffs; the only way to survive it is to make sure you're as diligent as possible with healing.
** Any attack that can [[StatusBuffDispel remove all buffs]] from the party can be this depending on what the boss can follow up with, but special mentions go to the following:
*** Luminiera Omega's Blade of Light, which randomly hits for big damage five times, fully dispels the party, and as the cherry on top, it paralyzes a random party member. If you're unlucky, this can come right after Aegis Unmerge, making her attacks much stronger and turning Blade of Light into a TotalPartyKill instead of just a full dispel.
*** Anubis's Ophois, which hits the whole party, removes all buffs, and has a chance to lower multiattack rate and debuff resistance and/or, even worse, inflict Zombie on them. What makes this one so bad is that Anubis is guaranteed to use it at least five times during the fight, and it gets progressively stronger the lower its health gets, to the point of needing some heavy damage cuts to tank it near the end.
*** Europa's Floral Prison doesn't do damage and only dispels one character as opposed to your whole party, but it makes up for this with the two status effects it also inflicts on the unlucky target; Azure Spike and Held Under. The former makes any attacks from the character ''heal Europa'' (and there's no way to stop them from attacking unless a status effect prevents it), while the latter prevents any healing on them, lowers their accuracy, and makes them take heavy damage each turn.
** Avatar has Archenemy, which is Skyfall taken to the extreme -- ''one hundred million'' dark damage to all allies. Fortunately, it only uses it once.
** Lu Woh's Flashpoint Trajectory, which is a TotalPartyKill that also affects the backrow. There are other raids that have attacks like this, but they exist solely to say "you messed up, now do the raid over". Flashpoint Trajectory, meanwhile, is ''a regular move that Lu Woh can use at will'' below 40% health. While it's possible to cancel this move, doing so requires hitting Lu Woh '''99''' times in one turn.
* In ''[[{{VideoGame/LISA}} LISA: The Painful]]'', "Neck Break", "Heart Squeeze", "Fatal Chomp", and "Decapitate". These are the only four moves in the game that can [[{{Permadeath}} permakill]] your party members, even if they're at full health. The worst part is that, while most bosses are obviously capable of using these moves, many random {{Mooks}} are also able to use these to completely wreck your party composition at a moment's notice.
* In ''VideoGame/ShadowHeartsFromTheNewWorld'' both the strongest BonusBoss and FinalBoss have a move called Lost Progress. True to its name, it's a StatusBuffDispel. The problem is that the bosses will use this ''instantly'' when you cast a StatusBuff - they just get a free turn as soon as you use a buff to cast Lost Progress. Because the developers thought that wasn't enough, the bosses then get ''another free turn'' immediately afterwards. You essentially ''cannot use buffs'' against these two bosses as a result.
* The postgame of ''VideoGame/BugFables'' has a fight with [[spoiler: Stratos and Delilah]], the latter of the two able to brandish a [[{{BFG}} bazooka]] and assault your party with a flurry of status-inflicting ammunition. It can hit up to ''12 times'', each hit dealing high damage (especially in hard mode) and guaranteeing a status on a bug unless you time your guards well enough. In addition to being able to take out an entire bug's health pool, it can inflict 2 new status effects that can either prevent item or skill use, and are incurable by most means.
* ''VideoGame/OctopathTraveler'':
** The dragon at the end of H'aanit's Chapter 3 can use Swept Away, removing any one party member from the field for several turns. If it's your main healer, you're in serious trouble. Later on in the fight, the boss' ultimate move lets it do this to ''two party members.''
** The Devourer of Men can use Spirit Away, removing any one party member from the field until the Devourer is broken. ''It can use this move multiple times to remove multiple party members.''
** When its HP gets low enough, the Ogre Eagle will unleash a poison upon the whole party than cannot be cured and will gradually lower the party's max HP.
** Ophilia's final boss can unleash a dark flame that disables the party's area magic until being broken, which is especially problematic for healers. Given that it cannot be cured by an apothecary, the attack has the potential of turning a pretty average boss fight into a borderline ThatOneBoss.
** Granted, it's otherwise an easy boss fight, and if you're constantly applying pressure, Darius will really never get a chance to use it, but God help you if you let Darius get off his super attack; he ''steals every party member except [[FragileSpeedster Therion]]'', (if Therion is dead when this happens, enjoy a TotalPartyKill instead) which is ''really bad'' because Darius attacks three times a round, more than enough to knock Therion on his ass. Mercifully, [[AntiFrustrationFeatures while Darius constantly swaps his weaknesses, he'll always retain a weakness for daggers, a weapon Therion will always have on him, and the party members are returned if he's broken.]] What's ''not'' so merciful is that Darius has access to Unconsciousness attacks; if Therion is alone, Unconscious, and Darius has more than 2 points remaining until he breaks, you've functionally already lost.
** Any [=AoE=] attack that has a chance to inflict Unconsciousness is this. Unconsciousness functions like Sleep, except the status doesn't wear off if your character is attacked. If your entire party is Unconscious, it's all but Game Over. Examples include Mattias' Black Thunder, Darius' Hellfire[[note]]Strangely, Lucia has the same attack, but it can't inflict Unconsciousness[[/note]], and Redeye's Bestial Roar[[note]]In fact, the last one is a bigger threat than Evil Eye, Redeye's Petrification skill, if only because Redeye can use the former from the start while the latter begins to be used after Redeye is down to 50% of its max HP[[/note]]. Better come prepared with a Conscious Stone!
* ''Monster Girl Quest! Paradox'' has Monster Lord's Cruelty and its stronger variant, Eternal Darkness, which basically have every annoying feature an attack can have. Monster Lord's Cruelty is Dark-element, so it [[AlwaysAccurateAttack can't be dodged or reflected]], [[ArmorPiercingAttack ignores Defense]] and [[InfinityPlusOneElement is hard to resist]]. It hits the whole party, so you can't limit it to one character with DrawAggro abilities. It hits four times, so you can't use [[SingleUseShield deflectors]] (which a character can only have two layers of) to survive it. It does major damage, enough to kill most of the time. And each hit has a 10% chance of instant death, so you can potentially die even if you survive the damage. Eternal Darkness is similar except it hits six times! The best way to survive these attacks is to have Nightmare characters in the frontline, since they're [[NighInvulnerable immune to everything except Pleasure damage]]. The second-best way to "survive" them is to have at least one character with an auto-revive, so they die and get revived afterwards.
* In ''VideoGame/ValkyrieProfile'', any enemy with the Great Magic spells will have it as its That One Attack, such as Akhetamen's Seraphic Law, Wraith's Gravity Blessing, Barbarossa's Calamity Blast, etc.
** While several of the NintendoHard extra bosses have similar moves, the final three of Lenneth, the Ethereal Queen, and Freya are by far the worst. With Lenneth and the Queen, you at least have a slight chance of making it to the edge of the screen to dodge Nibelung Valesti and Celestial Star. Freya, however, will spam Ether Strike again and again without warning and cannot ever be disrupted. You only hope is certain stunning items which buy you a total of three seconds before she's back on the offense.
** Almost every attack [[ThatOneBoss Bloodbane]] has qualifies. He will often follow up a damaging claw swipe ''("I'll crush you!")'' with Feel My Flame, which deals huge damage to the entire party. Occasionally he will follow this with a magic spell like Sacred Javelin, most likely killing one of your Einherjar. And when taken down to below half HP, he will start spamming the Great Magic Gravity Blessing, which can cause a TotalPartyKill. Adding insult to injury, he will heal himself to full once his health dropped below 25%, better unleashed whatever you have to take him down quickly.
** Fenrir in the [[GoldenEnding A Ending]] has Frost Bait, which it uses when [[TurnsRed at low health]] and deals huge damage with a chance of freezing anyone hit. A special item from the mid-game can stop it from freezing your party members, but it won't do much against the damage. The Fenrir clone in the [[BonusDungeon Seraphic Gate]], [[NamesToRunAwayFromReallyFast Carnage Beast]], can use Frost Bait both at full health and low health. Encountering two Carnage Beasts and having them do two Frost Baits in a row is likely to result a TotalPartyKill unless you have [[GameBreaker the Guts/Auto-Item/Union Plume combo]].
** The TrueFinalBoss, [[spoiler:Loki]], has two: Extension Force, which deals a single devastating blow to each party member; and Dragon Orb, a unique Great Magic that is just as painful as the rest.
** The [[KillerRabbit Hamsters]] in the Seraphic Gate have Furry One, which tramples the party under a wave of hamsters for ludicrous damage.
* ''VideoGame/WildArms'':
** The game has a take on [[Franchise/FinalFantasy Bad Breath]] called "Arc en Ciel" which does some damage along with said status blast. Expect it to be used by [[DemonicSpiders the aliens]].
** [[BonusBoss Ragu O Ragla]]'s Volcanic Bomb in the first game, which deals 7000+ fire damage to all party members and is unsurvivable without absolutely insane amounts of grinding. The only other ways to withstand it is to make sure at least Cecilia is always equipped with a Goat Doll, or find Frog Badges, which nullify elemental damage.
* It's not unheard of in ''VideoGame/WorldOfWarcraft'', either. Deathbringer Saurfang, for example, has an ability called "Mark of the Fallen Champion". Players marked by this ability will take massive damage for the rest of the fight, and if they are killed, he will heal himself for a significant amount. You basically just have to [[LuckBasedMission pray]] he doesn't target a SquishyWizard, or you're screwed.
** The bosses of Mount Hyjal seem to have this fairly often. Rage Winterchill, the firt boss, has a Death and Decay that does 15% of each victim's ''maximum'' health per tick. Azgalor has an attack that targets a player every 45 seconds and kills them after a 20 second debuff expires. Archimonde can fling players into the air with Air Burst, and they must know how to use the Tears of the Goddess correctly, or they will fall to their deaths.
*** Because of multiple That One Attacks coupled with his status as ThatOneBoss, Archimonde was considered unfarmable by some servers, even after he was nerfed for ''Wrath of the Lich King''.
** Toward the end of Wrath, if you mentioned the word "Defile" in trade chat, everyone knew what you were talking about. To those not in the know, Defile is an area of effect attack used by the Lich King. He frequently casts it beneath a random player, and its damage ''and size'' increase every time someone stands in it even for one tick. If your 25 player raid group mismanages this ability? [[TotalPartyKill You're dead]]. To make matters worse, he has ''another'' attack that is handled by ''stacking close together'', and since both attacks are on a slightly different timer, they occasionally come out back-to-back. Defile is the reason that, even at the end of the next expansion, when a single character has ten times more health and can output more damage than an entire raid party used to be able to, it still takes a coordinated effort to defeat the Lich King.
** Even going as far back as classic, [[EldritchAbomination C'thun]] had his infamous Eye Beam attack, which would blast a player for respectable damage before bouncing to another, ''its damage doubling each time''. Many stories were recorded about entire 40 man raid groups entering the room at once and getting slammed by this, the very last victims suffering hits in the ''hundreds of millions''. This attack may qualify in-universe for Memetic Badass status, to the point where people have sat down and thought up strategies to maximize its damage, such as taking 40 hunters with 40 pets and having them drop 40 Snake Traps.
** Garrosh Hellscream has Touch of Y'Shaarj, a MindControl effect that he puts on certain players. While afflicted players can be broken out after taking enough damage, they will mainly attempt to put the mind control on other members of the party, and if they get off a cast, the situation will spiral out of control. Once Garrosh gets enough energy, it gets Empowered, resulting in the mind-controlled players having more health and becoming immune to stuns, making it harder to interrupt or free them.
** On Heroic, Wavebinder Kardris of the Kor'kron Dark Shaman encounter uses Iron Prison, an attack that [[OneHitKill does 100% of your maximum health in damage]]. You can only survive it by being topped off and using a defensive cooldown, while also avoiding all the rest of the raid-wide damage.
** While the new version of Karazahn is meant to be brutal from start to finish, Attumen the Huntsman in particular has inspired more healer rage on the forums than all the other bosses combined. Why? A fun little mechanic called "Intangible Presence." It places a ghost on one member of the party, which deals heavy damage over time to everyone. If the healer doesn't dispel it quickly, the party will probably wipe. Every time the healer dispels the wrong person, however, they explode, dealing about a quarter of a typical DPS or healer's health to everyone. The cooldown on dispels also means that cleansing the wrong character guarantees another 8 seconds of the DoT, meaning the party will probably wipe. Of course, the "obey the mechanic or die" check is pretty standard for high-end dungeons and raids. The real problem is how difficult it is to see the ghost which is, well, rather intangible. This problem is only compounded with certain specs that have graphical effects that make it more difficult to see, like shadow priest and bear druid, to say nothing of certain trinkets whose effects actually look a whole lot like the ghost.
* Players of ''VideoGame/YggdraUnion'' often cringe when the word 'Genocide' is mentioned. It's the signature move of ThatOneBoss Gulcasa which kills off his allies, giving him an exponential boost in power for every unit killed. To make matters worse, this move shatters your meter, preventing you from using any cards to defend yourself with. Finally, if he manages to take out all your characters with this move during a skirmish, your morale takes quite a plunge. And you have to face this guy quite a few times. It's possible to get a character that is effectively immune to Genocide, but the route split happens ''before'' you first encounter Gulcasa.
** Players of ''VideoGame/BlazeUnion'' may cringe when the word 'Jihad'[[note]]English-speakers that played Yggdra Union may call it Crusade instead[[/note]] is mentioned. It's the signature move of Ordene, which immediately causes him to win if he is alone and at MAX Rage Rate. Oh, and you can't block it with Shield Barrier. Good luck with that. [[spoiler:There's a way around it; he won't attack Aegina with it.]]
** BonusBoss #367's Judgment Zero. In her first form it's barely worth mentioning, but in her second form it is practically guaranteed to do Overkill damage, which is an instant loss for you. Like Jihad, it is unblockable and non-elemental, so if she gets it off you ''will'' die. It's a lot more manageable in Blaze and Gloria, where it will only deal Overkill damage if Alanjame or Gariored is alone.
** Gloria Union has Megiddo. It's basically Crusade with a smaller Morale damage bonus, but its user doesn't have to be alone. Once again, it's non-elemental, and Shield Barrier and the new anti-Skill skill Magic Shield do nothing against it.

* Many examples in ''VideoGame/TheLordOfTheRingsTheThirdAge''.
** The Balrog has two, but they're really two shades of the same attack: Pillar of Wrath and Scorching Inferno. Both of them hit every member of your party, and both will drain almost all of the AP your characters have.
** Stomp from the Mûmakil. Hits everybody, and stuns them. Stand Fast makes it mostly worthless (it's still painful), but if it gets it off before Berethor gets a turn... Well, you're [[TotalPartyKill screwed.]]
** The Final Boss, Sauron, has 2. Darkest Fear immobilizes one of your guys and deals damage over time, and Berethor's Immune to Fear Passive ability and Shield of Courage Leadership do not work to stop it, unlike regular Fear. Silence of Light also immobilizes your entire party's Spirit skills. It's a huge pain, since most of your best abilities are Spirit, and you need them to last long enough to kill him.
* Despite being fairly easy overall, ''VideoGame/GoldenSun'' has several examples.
** ''The Djinn screws'', which put the targeted character's Djinn into recovery mode and thus prevents them from being used for unleash attacks and summons. Dim Dragon Plus' Djinn Burp is too soon to be a threat to the player, but literally every other attack which tampers with the player's Djinn without their consent is a pain in the ass.
*** Djinn Blast puts all of a single character's Djinn into recovery mode, resetting one by one with each passing turn. The Chaos Chimera from ''Dark Dawn'' and the Doom Dragon from ''Lost Age'' use this.
*** Djinn Storm is Djinn Blast aimed at the entire party. The Doom Dragon and Dullahan love this one.
*** The Star Magician in ''Dark Dawn'' can summon a Ghoul Ball, which eats a single Djinni each turn it's out; any Djinn it eats stay in recovery mode until it is killed, and it can summon multiple. Have fun.
** Cruel Ruin from ''The Lost Age'''s [[FinalBoss Doom Dragon]]. It works like your SummonMagic in that it deals more damage to targets with higher max HP, so no amount of level grinding will save you from it.
** Valukar has one that would be ThatOneAttack if it wasn't for ArtificialStupidity: he can use your summons against you, but tends to do so when you have only one or two djinn on standby, doing less damage than he would with his own spells. However, he can give you a nasty surprise if you depend on this overmuch.
** Almost ''every attack'' used by [[BonusBoss Dullahan]] counts as That One Attack. Dark Dawn might have been disappointingly easy, but Dullahan somehow got even harder.
*** It can use Charon, a summon-type attack that works identically to your version: high earth-elemental damage that has a chance to OneHitKill its targets.
*** Formina Sage/Fulminous Edge is a physical attack that hits for almost three times its normal damage. Even tougher characters like Garet will have a hard time surviving this.
*** True Collide is a spell that doesn't deal a whole lot of damage compared to the other two, but is still fairly dangerous, hits up to three characters, and [[LifeDrain will restore its health equal to the damage it inflicted.]]
*** In ''[[VideoGame/GoldenSunDarkDawn Dark Dawn]]'', it can steal your summons and use them against you, forcing your Djinn into recovery mode as if you'd used the summons.
** The Ancient Devil's Demon Sign [[BrainwashedAndCrazy takes over one of your characters]]. And they can use your djinn for summons, though they won't always do this. And since he targets the fastest party member with it, you're prevented from using Sveta unless you like suffering.
** The Chaos Chimera has Retribution, a reasonably strong attack which hits the entire party. It also has a chance of causing instant death. Oh, and the Chaos Chimera always attacks three times in a row. Have fun.
* [[OneHitKill Cunning Blow]] in ''VideoGame/MagiNation''.
* In ''VideoGame/ValkyrieProfile'', any enemy with the Great Magic spells will have it as its That One Attack, such as Akhetamen's Seraphic Law, Wraith's Gravity Blessing, Barbarossa's Calamity Blast, etc.
** Almost every attack [[ThatOneBoss Bloodbane]] has qualifies. He will often follow up a damaging claw swipe ''("I'll crush you!")'' with Feel My Flame, which deals huge damage to the entire party. Occasionally he will follow this with a magic spell like Sacred Javelin, most likely killing one of your Einherjar. And when taken down to below half HP, he will start spamming the Great Magic Gravity Blessing, which can cause a TotalPartyKill. Adding insult to injury, he will heal himself to full once his health dropped below 25%, better unleashed whatever you have to take him down quickly.
** Fenrir in the [[GoldenEnding A Ending]] has Frost Bait, which it uses when [[TurnsRed at low health]] and deals huge damage with a chance of freezing anyone hit. A special item from the mid-game can stop it from freezing your party members, but it won't do much against the damage. The Fenrir clone in the [[BonusDungeon Seraphic Gate]], [[NamesToRunAwayFromReallyFast Carnage Beast]], can use Frost Bait both at full health and low health. Encountering two Carnage Beasts and having them do two Frost Baits in a row is likely to result a TotalPartyKill unless you have [[GameBreaker the Guts/Auto-Item/Union Plume combo]].
** The TrueFinalBoss, [[spoiler:Loki]], has two: Extension Force, which deals a single devastating blow to each party member; and Dragon Orb, a unique Great Magic that is just as painful as the rest.
** The [[KillerRabbit Hamsters]] in the Seraphic Gate have Furry One, which tramples the party under a wave of hamsters for ludicrous damage.
* In ''VideoGame/DigimonWorld3'', even some normal attacks are that one attack. Mamemon's normal attack can freeze your Digimon, with a very high chance of blocking it from doing anything. Even better: it blocks you from healing your Digimon. Depending on your luck, you'll just mash X until your Digimon die.
** Hi Andromon has Atomic Ray, which has a solid chance of causing death regardless of your defenses.
** Pharaohmon, the very first boss, has Necro Mist, a move that not only deals high damage, it also has a almost sure chance to poison your Digimon. Wouldn't be so bad if Poison didn't eat 25% of your HP every time you get a turn.
** Vademon has an attack that has a good chance of putting your Digimon to sleep. Unlike in ''Franchise/{{Pokemon}}'', sleep makes it impossible to escape and definitely impossible to attack, making your Digimon a sitting duck for Vademon.
** There's also Bastemon/Persiamon, used by the Game Master, whose special attack, Helter Skelter, ''dedigivolves'' your Digimon to its Rookie form, harshly slashing your stats. You can re-digivolve to that form immediately afterward, but good luck getting an attack in before Persiamon uses it again.
* ''VideoGame/DigimonWorldDawnDusk'' has Chrono Destroyer, only useable by the final boss. High Dark damage, plus it can easily put your whole party to sleep. Also, Royal Slash is a Holy attack so strong that, in the more active era of the metagame, any player with more than one digimon with the move would be disqualified.
* ''VideoGame/DragonQuest'':
** You'll be hard-pressed to find a veteran player of the franchise who ''doesn't'' hate Disruptive Wave with a passion. Once the enemy uses it, ALL your [[StatusBuff buffs]] are gone and there is NO way to block it, leaving you with a huge disadvantage if you spent the last three rounds casting buff spells, which you absolutely ''need'' in the endgame, and need a heal badly. Especially if the enemy can attack more than once in a single turn, which by the second half of the game, most of them can! First turn, Disruptive Wave = Goodbye all defense and power boosts. Second turn, you get hit with an ungodly powerful attack. [[LuckBasedMission Have fun getting around that]].
** ''VideoGame/DragonQuestI'':
*** If the Dragonlord manages to connect with Stopspell, just reset the game; you ''need'' Healmore to defeat his second form.
*** If a monster knows the spell Sleep, be prepared to potentially lose a huge chunk of your HP. Unlike enemies, which can have Sleep resistance, you don't get that luxury. Even worse is if you're playing Dragon Warrior Randomizer, where enemies can and will use fire breath or Hurtmore (Sizzle) in tandem with Sleep.
*** In the Randomizer based off this game, there's a chance any monster, besides the first Dragonlord form, can carry Dragonlord's breath attack. [[note]]If you don't have Erdrick's Armor, it deals 65-72 damage to the player. When the player finds it, it deals 33% less damage, which is still dangerous to them, even on low HP seeds.[[/note]] Even the lowly Slime, of all things, can be extremely deadly early on. There's no knowing which monsters have it until it's too late. Thankfully, they will not use this ability if they have a weaker breath, Hurt/Sizz or Hurtmore/Sizzle.
** ''VideoGame/DragonQuestIII'': Expel/Blasto is found on only a few enemies and usually misses, but if it hits it knocks the character out of your party, and not just for that fight. You have to go all the way back to the first town to get them back. One of the "few enemies" to have it are Hades Condors, which are ridiculously common in the North American area.
** [[spoiler:[[BigBad Corvus]]'s]] Magic Burst in ''VideoGame/DragonQuestIX''. It converts all his remaining MP (Mana Points) into a blast that hits your entire team for (2*Remaining MP). ''And he can restore all his MP right after, every time''. And with his 255 MP maximum, it can ''easily'' oneshot the SquishyWizard of your team.
** And what if there were an attack that could insta-kill your entire party 100% of the time with no need for any softening up. It's generally limited to earlier installments, but the Sacrifice and Kamikazee spells can do this. Once an enemy chooses to cast one of these, it's an instant Game Over. ''VideoGame/DragonQuestII'' even gave these spells to common Mooks, meaning that you could be wiped out because you looked at them funny.

* ''VideoGame/WildArms'':
** The game has a take on [[Franchise/FinalFantasy Bad Breath]] called "Arc en Ciel" which does some damage along with said status blast. Expect it to be used by [[DemonicSpiders the aliens]].
** [[BonusBoss Ragu O Ragla]]'s Volcanic Bomb in the first game, which deals 7000+ fire damage to all party members and is unsurvivable without absolutely insane amounts of grinding. The only other ways to withstand it is to make sure at least Cecilia is always equipped with a Goat Doll, or find Frog Badges, which nullify elemental damage.
* ''Franchise/KingdomHearts'':
** In every game, Riku has an attack entitled Dark Aura, wherein he'll become invincible and fly in quick dashes at your character, before then slamming into the ground and sending out bursts across the area. It does heavy damage and is very hard to dodge. It's even more devastating in ''Chain of Memories'', although you do have 0 cards that can break it. It also helps that in Reverse/Rebirth [[GameBreaker you can use it yourself]] ''[[GameBreaker as]]'' [[GameBreaker Riku]]. Also, Ansem's ultimate attack in Riku's last battle with him will almost certainly be fatal unless you dodge it.
** BonusBoss [[VideoGame/FinalFantasyVII Sephiroth's]] "Heartless Angel" attack, which drains all of your HP and MP in one shot. If you aren't able to interrupt it, you '''need''' the ability that lets you survive lethal blows with 1 HP (Most people assume it's a HPToOne attack because they haven't turned Second Chance off since they first got it ''way'' back in the beginning), but then you still have no MP to heal with. ''Ouch.''
** The second game gives Sephiroth an opening move that you have to block with an ActionCommand, otherwise you die. At least you don't lose ''that'' much progress if you mess up.
** [[BlowYouAway Xaldin's]] Wind Dragon in the ''VideoGame/KingdomHeartsII''. Multi-hit so it gets around Second Chance, does high damage, and is nigh-unavoidable. Thankfully, Reflega works perfectly well to shield you from it.
** ''VideoGame/KingdomHeartsBirthBySleep'' has the nameless [[BonusBoss optional boss]] [[RegionalBonus that the Japanese didn't get]]. This boss has Collision Magnet. Basically, the boss hauls you in with a rope and deals damage in mid air. First, it hurts. You need to be at a high level for this attack to not instantly bring you to your final Hit Point. Second, it's very fast and difficult to see coming, and unblockable. Third, it leaves you open for another attack, which can kill you if the rope managed to get you to one HP, without you being able to recover; even if you have Once More, because apparently the next attack, which you don't have enough time to recover for, counts as a separate combo. Your chance of victory is inversely proportional to how many times this boss decides to use this attack. This move was so bad that when the Japanese got their inevitable [[NoExportForYou Final Mix]], they nerfed this move to allow you enough time to dodge or heal, mainly to make the two ''new'' bonus bosses look challenging next to him.
** The "[[FanNickname Rape Rope]]." It's telling that the tracking for it is so good that if you use or spam your dash/dodge move (which has invincibility frames and moves you very quickly), the rope will just latch on your character as s/he's dodging ''continuously for several seconds'' if you're able to keep it up for that long, so that it grabs you as soon as you run out of invincibility frames.
** Collision Magnet has jack and shit next to the Doom spell. Doom is when the Unknown throws out a few lines that if they ensnare your hero, you have to mash the X button (Circle in Japan) to break free. Thing is, Doom's countdown isn't consistent. Sometimes, it'll be 5 seconds to death, but on other occasions, it's 2 with a swift timedown cause. Unless you can smash buttons with the best of them, getting snared by that move is a death sentence with no way out of it. Compounding the real issue with Doom is that the move can come out VERY quickly, like after you just hit him with a surge art or when he's recovering and performing another move. Sometimes you just straight up lose if Doom hits you and you physically cannot mash the X button fast enough to break free.
** A lot of bosses in this game have some kind of inescapable stun-lock combo that in proud or critical difficulty will leave you with little to no health, requiring Second Chance/Once More and some form of healing ready. To make matters worse, HP isn't given by leveling up but instead is based on story events or through the HP up ability, and getting the latter can be a "LuckBasedMission" or require grinding through an optional area. Leveling doesn't really help your survivability because defense is pretty negligible in the higher difficulties and you even get less than the standard or easy difficulty. Some bosses with combos like this: [[spoiler:Terranort, Master Eraqus, Zack Fair, Braig, Vanitas, the Deep Space Boss, etc.]]
** The Armor of the Master and No Heart from the final mix of ''Birth by Sleep'' each have their own. [=AotM=] has a 20 hit combo almost guaranteed to reduce your HP to one normally, but if he's been allowed to enter his SuperMode by sapping you with his chain, it's a guaranteed kill. No Heart's ultimate attack is basically a dark version of [[SphereOfDestruction Mega Flare]] ([[Franchise/FinalFantasy Shadow Flare? Ultima?]]), which he starts using late in his battle. It's uninterruptible but can be avoided, but if you either fall into one of his [[StatusEffects Slow]] traps or are right next to him when he rises into the air, you will be hit. Like Sephiroth's Heartless Angel, getting hit by this move means instant death if you don't have Second Chance, and even if you survive, it [[ManaBurn burns out your Focus gauge and all your commands]]. This is also a guaranteed kill if he uses it twice, unless you have an item which you'll likely have [[MarathonBoss used up by then.]]
** Ever wonder why everyone hates [[spoiler:Terranort]] so much? Because he has a ''really'' annoying combo that stun-locks you and takes away most of your health, and even has two non-consecutive blows that can ''[[TheComputerIsACheatingBastard bypass]] [[LastChanceHitPoint Second Chance/Once More]]'' if your HP was already depleted to one by then. [[spoiler:It's the same combo that Terra uses himself when in Dark Impulse mode, but unlike Terra,]] he can pull this combo off ''at will'', and this makes it ''very'' hard to hit him. He also has [[spoiler:Ars Solum. How is it different than Terra's version of it? Well,]] it's unblockable, it is difficult to knock him out of it, and he can use it up to '''THREE TIMES IN A ROW'''. [[spoiler:Of course, when ''you'' use it, he just blocks the first hit of it, and Counter Hammers you.]]
** In addition, Zack performs Omnislash. You may feel pity for those hordes of enemies you murdered like that. It's used at the start of the battle, and can be used again during the battle. You are given a clue that tells you it's coming, and it's STILL hard to dodge.
** The optional boss from ''VideoGame/KingdomHearts358DaysOver2'', the Dust Flier, has an entire arsenal of these. First, there's a shockwave that will deal a random status ailment, a bombardment attack that comes fast and knocks you around like a ragdoll, AND the charge attack. The charge hits like three Mack trucks slamming into you one after the other. Glide makes it much easier to dodge, but you still have to deal with the Flier's [[MarathonBoss ludicrous HP count]]. If you can bring down this airborne bastard, you've earned the right to trash talk.
** The Mimic Master's laser attack in ''VideoGame/KingdomHeartsBirthBySleep''. He fires off two lasers, one bright and the other dark. If the dark one hits you, your field of vision is reduced and you lose the ability to lock on (as well as your Shotlock). It's also floor-level, so you need to jump over it and hope the bright laser doesn't catch you (although that just deals damage). Trying to run away from it? Don't bother, it takes up just about the entire field! And the Master is invincible for the duration of the attack.
** Both Demyx and his dancers fall into this:
*** [[MakingASplash Demyx]] from ''VideoGame/KingdomHeartsII'' has a ''very'' annoying attack where he says, ''"Dance, water, dance!"'' and you have to kill ten water clones of him in ten seconds (fifteen seconds in ''Final Mix''). Fail to do so? Game Over, with [[NonstandardGameOver no explanation as to why]]. It will probably be the biggest cause of frustration for you when you fight him. Though at least the increased timer in ''Final Mix'' makes destroying the clones ''slightly'' more manageable.
*** Demyx's Nobodies, the Dancers, have a nasty trick as well. Once they've taken enough damage, they will skate across the ground toward you while orbited by motes of light. It they make contact with you even for a split-second, they'll grab you and hit you with a throw attack that does quite a bit of damage, tosses you pretty far, and also interrupts any combos you're hitting other enemies with. And it can't be guarded against.
** There's also BonusBoss ''Kurt Zisa'' from ''VideoGame/KingdomHeartsI'' and his infamous ''Silencega'' technique, which is able to completely lock your magic -- until you destroy the two crystal balls in his hands. His hard-hitting physicals make healing very important -- for which you have nothing but items, which can't be shortcutted in this game. [[GameOver Game Over]] is imminent.
** [[spoiler:Anti Black Coat Nightmare]] in ''Dream Drop Distance'' has a particularly irritating one: he'll fire out a thin red line along the ground. If it hits you, it will lift you up in the air, ''[[HPToOne suck all but 1 HP out of you]]'', and ''scatter it around the arena as HP orbs!'' So, basically, you have to pick up all your health, ''while he's still attacking.'' Oh, and it's sometimes possible for him to use that attack just after he fires a barrage of weak shots. Immobile and on 1 HP, you have no chance of avoiding death in that situation.
** BonusBoss [[WesternAnimation/RunawayBrain Julius]] has a pretty big one too: he'll charge himself up with lightning, jump to the top of a tall building, then leap back down and bounce along the ground. It's really hard to avoid because of the AI's uncanny ability to know exactly where you're going to be when he jumps, so he usually ends up landing right on top of you. But that's not the worst thing about the attack. If he hits you, a random one of your commands will become greyed-out and have its reload rate slowed down so massively it's essentially taken out of the battle. Lord help you if he gets all your Curagas this way. Especially annoying is that, 9 times out of 10, the camera will lose your lock-on to Julius when he jumps, so you can easily get stomped simply because you lost track of where he was.
** The Data versions of the Organization battles in ''VideoGame/KingdomHeartsII [[UpdatedRerelease Final Mix+]]'' all follow a distinct formula, unlocking a very powerful attack (frequently called [[FanNickname desperation attacks]] by the fandom) once you damage them enough. The game will force you to deal with this, and sometimes will not let you defeat the boss until you have triumphed over this attack (Demyx's 'defeat 99 water clones in 30 seconds' and Luxord's 'Do you know the rules?' minigame are good examples: do what you like to their HP, but you won't win until you clear those challenges). If you're lucky, the boss in question will only use this desperation attack once (like Demyx and his final water clone challenge). If you're ''un''lucky, which you usually are, it will be added to the boss's pool of moves and reappear as often as the boss wishes. For example, Data Xemnas gets 'Can you spare a heart?', the move he used in the FinalBoss battle as a one-time scripted event/gameplay element (the one where he drains Sora's health and the player is forced to use Riku), as a desperation attack, that he can use as often as he pleases after his health dips below a certain point. The good news? Since it is no longer a scripted event but a regular attack, it can now be blocked by Reflect, or Limits (as Sora is invulnerable while executing a limit). The bad news? You had ''damn well better block it'', because Xemnas will drain Sora's health so fast this move might as well be a OneHitKill
** Xemnas as he appears as a bonus boss in ''Kingdom Hearts: Final Mix'' has an attack where he replaces all of Sora's menu commands with "Shock", which harms Sora, and "Release", which ends the move. Thing is, "Release" hops randomly and rapidly through Sora's commands, making hitting it without missing the timing and getting Shocked very tricky. In addition: the attack continually drains Sora's HP either way until "Release" is selected, Sora can't use magic or items to heal himself during this time. Oh, and Xemnas is still attacking. The move is initiated by a very fast melee attack that has little-to-no telegraphing time.
** Every single one of the Lingering Will's attacks are these, particularly one which is identical to Xemnas' attack above, as well as a hard to dodge, unblockable, poorly telegraphed move which can either prevent you from using magic (so no healing, no Reflega and no ranged attacks) or ''attacking at all''.
** The final battle with Master Xehanort in ''VideoGame/KingdomHeartsIII'' has a particularly brutal desperation attack. Once you get him down to two bars, he'll send you to a room similar to The World That Never Was where 13 shadow-y versions of himself all rush you after he gives the order "Expire". Blocking and dodging is insanely difficult.
*** Data Master Xehanort's version of this attack has him alternate between replica rushes and his other attacks. The timing is extremely precise, and failing to block or dodge one attack will most likely lead into getting hit by the next. He also gains a new set of X-Blade combos where one can stun Sora but even worse is the double-bladed attack where it is not only unblockable but will also reduce Sora's maximum HP, making it harder to tank other attacks.
** Saix's thrown Claymores are completely unblockable & stuns Sora on impact and in Critical Mode, will almost always reduce his HPToOne. This leaves Sora completely defenseless against his next attack without giving the player the opportunity to heal themselves, easily making his attacks the most punishable on Sora's end.
** Yozora, the BonusBoss from the ''III'' DLC ''Re Mind'' has one attack where he is capable of stealing your items. This is very difficult to anticipate and it range from either your HP to recover himself, your Keyblade which leaves you completely incapable of attacking or blocking his attacks, or even worse the AutoRevive Kupo Coin where not only he robs you of a potential extra life but when you somehow brought him down, he'll use it to ''revive himself with half of his health bars along with another layer of armor HP''.
* ''VideoGame/RomancingSaGa:'' Death likes spamming Open the Gate a lot; it kills your characters outright or heavily damages them.
** Or even worse: Jewel Blaster, which deals magical damage, not physical, and is Quad elemental. The Jewel Beast even spams it every three turns instead of six when you whittle his HP down. The "Overkill" you frequently see after Jewel Blaster isn't just for show.
** However the most annoying one is Animate Dead, it's a permanent charm effect until the character loses all HP and dies again.
* ''VideoGame/RomancingSaGa2:'' Rockbouquet's skill: Temptation - which charms all male party members.
* ''VideoGame/RomancingSaGa3:'' Maelstrom (Insta-kill unless wearing armor that is water elemental), Fatal Mirror - which turns characters against each other, and Howling, which revives a fallen party member to attack once.
* ''VideoGame/{{Drakengard}}'':
** When fighting Furiae, there's an attack where she sends a dozen swords at you. And you have to dodge every single one, or you take full damage. It is avoidable, if you use homing fire, or the dragon's fully-powered LimitBreak, but [[GuideDangIt you probably wouldn't know that on your first try]].
** Manah in the canon ending is a pain in the butt. She has this annoying attack in the middle of the fight where she summons rings that come from her abdomen, not too bad. However, after [[TurnsRed taking so much health from her]], she decides to summon the rings from all angles... Have fun dodging those.
* In ''VideoGame/SuperMarioRPG'', the Breaker Beam attack used by Axem Rangers and later Gunyolk. Luckily, it requires charging for a turn or so, so you won't get nailed by it twice in a row. The charge-up also allows you to defend for the next turn so you'll only take half damage.
** Some [[OneHitKill instant-death]] attacks can count as this, especially the completely unblockable ones. The less powerful ones can be blocked by certain accessories, and can also be blocked by proper timing. How well you time your defense is the difference between surviving it with only 1 HP and remaining unscathed.
** When Smithy is in his wizard form, Sword Rain, Spear Rain, Arrow Rain, Dark Star, and ''Meteor Swarm'' count heavily. Also, his chest form uses different status effects on you, and Tank Form has an instant death attack.
** [[MeaningfulName Yaridovich]] and his [[KillItWithWater Water Blast]] has downed many a low-level run player.
** Carni-Kiss is a ''really'' powerful attack. It's not a OneHitKill, but unless you explicitly do some grinding, it may as well be. And since it's ''technically'' a magic-based attack, you can't guard against it. A lot of the already-tough enemies like the {{Chest Monster}}s and [[StrongAnts Shogun]] pack it, which doesn't help matters. Very ironically, by the time you fight the [[MoreTeethThanTheOsmondFamily Chomps]] that know it, it's not as dangerous.
** Certain spells such as Petal Blast and Aurora Beam will damage your entire party as well as have a chance of disabling each member. In the worst case, your entire party can be disabled until each one either dies or the RNG decides that you shrug it off. At least Mushrooming lets you recover HP every turn.
** Bundt's Diamond Saw is powerful for that point in the game, and can potentially KO a character in one hit. This is especially annoying since the second phase of his battle you have to blow out his candles by landing an attack on him, where he re-lights a candle each turn, and if you lose a character this could be difficult. The battle is otherwise pretty easy if he ''doesn't'' use Diamond Saw.
** [[BonusBoss Culex]] and his elemental crystals have nothing but stupid-powerful attacks (like the aforementioned Water Blast), but none of them compete with his one physical attack. He doesn't even move to attack you, all that happens is you instantly hear a slash and one of your characters takes about 150 damage at a respectable level (for comparison, all of your characters are barely below 200 HP, and most of the magic attacks will only deal 50-70 at that point). And because of its unpredictability, it's impossible to block unless you instantly press A as soon as it's his turn to move. Even when you [[GameBreaker put the Lazy Shell on the Princess]], which lets her take little to no damage from every attack in the fight, this attack will still deal about 50 to her. There's also his Dark Star special as well, which can pose a serious threat even to a Lazy-Shell-equipped Toadstool. At least it's only single-target.
* In ''VideoGame/PaperMario'':
** The first ''VideoGame/PaperMario game'' has Tubba Blubba's heart attack (Though it can be dodged by using Outta Sight), General Guy's Lightning Bulb Shock (can be stopped by breaking the bulb), Huff n Puff's Lightning Shock (Which makes him immune to most attacks for a few rounds and does massive damage), and the Crystal King's Ice Beam attack (which does light damage, but inflicts the Freeze status effect on you). Finally, Bowser has several attacks, but the most frustrating one is his jump attack, which removes an option to attack from your menu (If you lose the Jump or Item one, you are screwed). Even the Koopa Bros' super attack is painful at the point you fight them. Also, Jr. Troopa when you face him in the Shiver Snowfield, when he uses his magic attack which does about 8 damage (which is powerful for this series).
** Also, any attack that can damage Mario's partner. In this game, none of Mario's partners have their own HP bar and if any of them are hit with a certain attack for a set amount of damage, then they will be out for that many turns (for example, getting hit by an attack that does 2 damage means they're out for two turns). This can quickly turn a fight one-sided against Mario. Fortunately, there aren't that many moves in this game that does it. The moves that are able to damage Mario's partners as well are Buzzar's whirlwind attack, Tutankoopa's Chomp Spell attack, Big Lantern Ghost's lantern shine attack, the already mentioned General Guy's light bulb attack, and Bowser's Star Rod shine attack. Interestingly, most of these attacks are light-based and Watt, the Lil' Sparky, is immune to these attacks.
* In ''VideoGame/PaperMarioTheThousandYearDoor'':
** Magnus Von Grapple 2.0 has the Audience Cannon, which deals ridiculous amounts of damage if you don't have plenty of Defense buffs active. And just like its name says, it shoots the audience at you, for 3 damage per shot (which adds up to over 20 damage, which is almost always fatal in this game). And the audience is what you get your Star Power (essentially LimitBreak) from. To a lesser extent, X-Yux has the attack that it uses when it has four mini-X-Yux around it, which deals massive damage and immobilizes; if it gets a chance to use that attack, the player is in serious trouble.
** The Shadow Queen's hands can use an HP-draining attack that deals 7 damage and heals 7 HP to the Shadow Queen, can be used once per hand, and ignores defense. If you get the timing perfect, however, it can be superguarded.
* In the ''[[VideoGame/MarioAndLuigi Mario & Luigi]]'' series:
** The first attack used by [[FinalBoss Cackletta during the final battle with her]] in ''[[VideoGame/MarioAndLuigiSuperstarSaga Superstar Saga]]''. Because if you don't dodge, you will die instantly due to [[HPToOne both Mario Bros. being reduced to one health point at the start of the battle]] (beforehand, you get blown up by a time bomb and eaten after a HeadsIWinTailsYouLose fight). This is, of course, if your speed is lower than hers. Otherwise, you can heal immediately after the battle starts. The chances of you being faster than her are pretty low, though, since you'd've had to have leveled up to around level 34 and/or really focused on speed when using the level up bonuses and/or be using a badge that increase your speed and/or used speed up stat items. Thankfully, the 3DS remake adjusted her speed down so that the brothers always have the first move unless they're massively underleveled.
** Two of Bowser X's attacks in ''[[VideoGame/MarioAndLuigiBowsersInsideStory Bowser's Inside Story]]''. One is where he becomes giant, chases you down, and you have to dodge both fireballs being thrown at you and others you have to jump over while escaping him. If you get hit three times, you get knocked out and he crushes you flat. His Shy Guy attack is also very nasty: it's kind of like a reverse Koopa shell, and if you miss, the brother takes a lot of damage. He also has an attack where he shoots fire, you hit it back, he turns into a fiery shell, drops a ton down from the sky that you have to hammer away, and then falls on you. If you do deflect his fall, he'll then fly off to land on the other brother. And he goes fast.
** In ''Bowser's Inside Story'', the Junker seems like a fairly standard FlunkyBoss... until he sucks [[ButtMonkey Luigi]] up and sticks him inside one of his flunkies. The attack is unavoidable [[note]]in the original version. In the 3DS remake, it was changed so that you can escape it by repeatedly mashing the B button, making the attack much more bearable[[/note]], unlike nearly every other attack in the game, and requires Mario to keep track of the Junker Can that Luigi is inside. In addition, the Junker Cans have tons of HP, they regularly swap Luigi around, and if Mario gets knocked out, you lose instantly.
** Dark Star/Dark Star X and its cloning attack. Generates five to seven copies of itself, then charges at each brother. However, the copies turn INVISIBLE a short while before they reach your character, and long enough that you have to guess when to strike too. Miss that attack, and you get hit quite hard, often by another copy following the first one. On the plus side, a successful defense will likely knock out the next clone headed for that brother too. The developers apparently really liked this attack, because it returned in ''[[VideoGame/MarioAndLuigiPaperJam Paper Jam]]'', this time used by King Boo.
** There's also the giant laser/fire breath beam attack used by five bosses in ''Bowser's Inside Story''; Bowser, Dark Star, Dark Star Core, Dark Star X, and Bowser X. It does massive damage to the point of almost being a one hit kill, but is usually easily enough dodged. However, if one brother is knocked out, and the other guy is holding him, then it's quite difficult to catch Starlow and go to the top screen, likely killing whoever's remaining. Oh, and Dark Star does a kamikaze type charge at Mario/Luigi/Starlow if you dodge the beam, so if you forget to drop back down to the floor, it'll likely deal the same amount of damage the beam did.
** The Elder Shroob Princess' last form in ''[[VideoGame/MarioAndLuigiPartnersInTime Partners in Time]]'' has an attack where her tentacle legs start spinning around her, forcing you to jump over them. It's not too difficult when she only has two legs, but when she has four legs, it's almost impossible to dodge. Couple that with the brothers flinching for a short time after getting hit so that once you get hit, it's impossible to ''stop'' getting hit, and you've got one incredibly annoying attack. Oh, and of ''course'' it does a ton of damage.
** In ''[[VideoGame/MarioAndLuigiDreamTeam Dream Team]]'', there are quite a few attacks like this:
*** One is Earthwake's flying hammer attack, where the boss turns into a gigantic mallet you have to dodge or smack away... multiple times. In Hard Mode, he even does about 10 of these swipes in one turn, so you can literally go from having full health to being dead just because you couldn't dodge/block a single annoying attack.
*** There's also Pi'illodium's hammer anvil style attack, where he flies off screen and comes down like a hammer on a Bro's head... at about 90 miles per hour. It's entirely trial-and-error-based, since you likely don't have the split-second reaction times to deal with it as it's about to hit, and even when you know, the timing is still rather unfair (and it can also stun the character it hits to stop them moving)
*** There's also two of Antasma's attacks in his final battle: the bat swarm and the rings of death. The former summons a huge flock of bats that fly across the level and have to be dodged (and due to the misleading depth/graphics style, you can't easily tell which ones are heading for you to begin with) or you risk [[DreamWithinADream falling asleep]] and having to escape an endless gauntlet of obstacles, while the latter has him throw rings of exploding orbs at Mario as he runs away, with you having to be in the middle of them and then jump the shockwave to avoid. The latter is arguably better if you fail than win, since being hit by the shockwave actually builds up to more damage than just being blown up to begin with.
*** The giant Mount Pajamaja volcano boss's ramming attack is less an attack than a free ticket for him to take out 1/4 of your health. He only does it once at a time (thank goodness), but if anything, it is even ''harder'' than Earthwake's hammer attack to counter. It requires repeated quick strokes on the touchscreen to defend against, and most of the time, these won't even register enough to matter.
*** The [[DemonicSpiders Beehoss]] have a counterattack they use whenever they're hit by something, which is to summon a swarm of bees that's hard to jump over. Counter-counterattack the bees by jumping on them instead of over? They'll hit you with an unavoidable counter-counter-counterattack. (Dear Zeekeeper, it's like [[VideoGame/MarioAndLuigiSuperstarSaga Prince Peasley and Fawful]] all over again.) Their regular attack works the exact same way, and while the tells are in the background (for the Bro. they target), sometimes they don't show properly and it's up to luck.
*** [[spoiler: Dreamy Bowser]] has a hammer attack of his own. He signals which Bro he will hit and slams the hammer down very quickly, requiring fast reaction times. After it gets hit back by your hammer he will then slam it down, at the same speed, on the other brother. Not only is it powerful it also generates a shockwave.
** From ''VideoGame/MarioAndLuigiPaperJam'':
*** The Paper Sombrero Guys only attack. They throw their hats at the Bros. in quick succession requiring rapid reflexes. There is also a chance the Guy will charge at you after throwing the hat to mess up your timing; there is no way to tell if this will happen.
*** Paper Boomerang Bros. may throw two boomerangs to circle one of the Bros. Countering requires both boomerangs to be hit ''simultaneously'' and there is only one point where they will both be in a position to be hit, which has a very small hitbox.
*** Shockwave attacks have become this now there are three characters to control. Dodging them completely now means there is SomeDexterityRequired.
*** Wiggler's combo of using shockwaves (see above) followed by seeds and ending with chasing one Bro as enemies knock them into Wiggler so he can trample them. Not dodging the last part of the combo will kill the unfortunate brother and the shockwaves and seeds can trip everyone up and may leave the other two hurting, near death or just dead. A TotalPartyKill is very possible with this attack.

* [[spoiler: Luther]]'s Insanity Prelude in ''VideoGame/StarOceanTillTheEndOfTime'', an unblockable red flood that covers most of the battlefield. Assuming you aren't about thirty levels overleveled with equipment you shouldn't even have, its multiple shots will kill your entire party easily - you can only avoid it by standing in certain corners of the battle map - and forget your AI-controlled party members going there, you have to guide them all manually. (Alternatively, you can stun him out of casting it.) Any message board for the game is inevitably hit with 'how do I dodge Insanity Prelude' more than a few times.
* While several of the NintendoHard extra bosses have similar moves, the final three of [[VideoGame/ValkyrieProfile Lenneth, the Ethereal Queen, and Freya]] are by far the worst. With Lenneth and the Queen, you at least have a slight chance of making it to the edge of the screen to dodge Nibelung Valesti and Celestial Star. Freya, however, will spam Ether Strike again and again without warning and cannot ever be disrupted. You only hope is certain stunning items which buy you a total of three seconds before she's back on the offense.
* ''VideoGame/OdinSphere'':
** Onyx's inferno charge can cross the entire arena (''twice'') and leaves a field of damaging flames in its wake; in addition, Oswald can't jump high enough to clear it. He also lunges at you if you try to jump to stop you. Heaven help you if Onyx decides to spam it.
** Brigan's grab attack isn't a OneHitKill, but it may as well be, dealing insane amounts of damage and dizzying you afterwards. Unless you've been chowing down with Gwendolyn to raise her max HP, if he grabs you, it's over.
** Belial's inhale attack, where he attempts to suck the player in and eat them for a lot of damage. This usually comes after he's filled the arena with junk, so there's lots of things to hit the player as they're trying to run away and knock them backwards (and of course {{Mooks}} aren't affected, so they're free to further help knock them into Belial's maw). On the plus side, if the player managed to get far enough to get behind him, they can wail on him with impunity.
** In Leifthrasir, the Phoenix Riders in Volkenon. There's an attack that they do that causes a pillar of lava to shoot out of the floor and send flaming debris everywhere. Since the pillar is almost as tall as the stage itself, expect a lot of rage if you get caught between it and the rider.
* ''VideoGame/BatenKaitos'':
** Fadroh is a CurbStompBattle. Who is curb-stomping who? That depends entirely on whether or not Fadroh buffs himself with Orb of Magical Offense.
** [[spoiler:Geldoblame]]'s Forfeit Your Life, a OneHitKO. And he likes to use another attack called Seal of Evil, which paralyzes a character, meaning they ''can't defend''.
** The Angel of Darkness also likes paralysis, but couples it with an attack that steals your HP. When he TurnsRed and moves twice per turn, it's not uncommon for him to heal faster than you can damage him.
** Agyo's A-Up Pentagram. Not a OneHitKill, but might as well be.
** The Holoholobird's Wingflail, which knocks the whole party down and breaks any combos you've set up.
** The Godcraft's hail attack. It hits the entire party for tremendous damage, enough to cut over half their health down. In what might be either a bug, a programming oversight, or just the dev team being sadistic, this attack (and several others used mostly by bosses) are ''lethal'' if you have a party member knocked out. Essentially, they're programmed to hit the whole party multiple times, but the targeting is random, i.e. the attack might not even scratch Guillo, but knock Milly out and put Sagi in the red. However, if one of the party members is down, the attack only has two targets, but it still hits the same number of times, meaning the two remaining are in for a world of hurt.
** [[spoiler:Wiseman]]'s Cast Off Your Carnal Robes. Doesn't do too much damage, but it knocks the whole party down, destroys any magnus you have equipped, and breaks your combos. Just to add to that, he steals your magnus power with his regular attacks, so you'll be seeing his specials a lot.
** Magnus of Life, used by [[spoiler:Verus-Wiseman]]. It hits the entire party, hurts like hell, heals the boss, and inflicts all status ailments. Nothing's better than losing just because everyone's blinded or frozen.
** The Hearteater, the boss of the Matar Highlands, has a particularly cruel attack called [[FaceFullOfAlienWingWong Ovulate]]. A character hit by it has a timer slapped on them which, when it hits zero, [[OneHitKill kills them instantly]] and runs down notoriously quick (often before your next character's turn even comes up). This is made even ''more'' frustrating by how the Hearteater loves to spam sleep attacks as well. Your only options to deal with it are to burn through Chalice of Freedoms, which drains MP so you can't use your specials, or constantly keep using Cordial of Fates to revive them at low HP.
** Even [[WakeUpCallBoss Giacomo's]] Thrashinggale will have you pulling your hair out, as at that point in the game the attack alone can drain half to three-quarters the health of any one character, the attack can be chained to a combo for a cheap kill, and it's too early in the game to have any decent recovery magnus aside from a small potion and fate's cordial. In later battles the "Thrashinggale Redux" is much easier to contend with as the [[VillainForgotToLevelGrind Villain Forgets To Level Grind]].

* The evil storyline of ''[[VideoGame/ChampionsOfNorrath Champions: Return to Arms]]'' has Mithaniel Marr as the FinalBoss. And one of his attack sequences involves throwing you to the ground while dealing immense damage, and then attacking several more times while you can't move. This only applies in single player mode, however, with two or more this attack is a great way to get a shot at his back.
* In ''VideoGame/{{Runescape}}'', the final boss of the quest Nomad's Requiem, the eponymous Nomad has an attack in which he freezes you in place, then charges an attack that does damage equal to your maximum health minus one hitpoint. There's no way to avoid it, and unless you have maximum health when it hits, you die, instantly. That was the case until "damage soaking", which made this attack less scary[[labelnote:Mechanics]]When you would be hit for 200+ damage, the part of the damage which is 200+ is reduced by several-severalteen percent, based on your armour. This usually is useless, but against Nomad, which can hit for 750 and for MAXHP-to-One, this actually makes some visible impact[[/labelnote]].
** Most of the Dungeoneering bosses are just normal bosses with One Attack that makes them special. The Luminescent Icefiend is notable - at every 25% HP milestone, it becomes invulnerable, then sends down a painful icicle rain attack[[note]]that takes just about two seconds to fall down and is fired at a rate of one per 0.6 seconds, which is as often as possible. The attack doesn't deal much damage per hit, but if you get hit by one, you are thrown aside and generally assured to be hit by a dozen more. Luckily, it stops before you die. The only way to avoid it is to keep moving - if you stop for even a second, bang. The fact it targets an area and not a player is especially frustrating - if you're in a large team, then crossing paths with someone can mean being hit by an attack meant to hit him[[/note]]. Night-Gazer Khighorahk has a melee attack that hits everyone around him for heavy damage, too - if you don't run away when you see it charging, you take heavy damage. Saggitare's arrow rain works the same way.
** Even player-killers have their own That One Attacks, such as Ice Barrage, which freezes the target in place, but can be cast over and over, lengthening the effect. It basically leaves melee fighters helpless.
* In ''VideoGame/{{Mother 3}}'', [[spoiler:Porky]] has an attack that he, thankfully, rarely uses where he "coughs something up." It is the equivalent of using Offense Down AND Defense Down against your entire party '''3 TIMES,''' and can be dangerous if you don't have enough PP to raise your stats back up.
** From VideoGame/EarthBound, you have the Kraken's tornadoes. They do huge amounts of damage, hit everyone in the party, and can't be nullified or deflected like his other attacks can. Also, buffs won't help you; the Kraken's only nonoffensive attack neutralizes any buffs or debuffs you might have cast.
** Also, Diamond Dog's 'glorious light' attack. Anyone without certain equipment will most likely get paralyzed, killed, or confused. You're in trouble if you missed the Sea Pendant at the far end of the Lost Underworld.
** Also is the "spread some spores" attack that mushroomizes an ally, which causes both InterfaceScrew outside of combat and [[UnfriendlyFire randomly striking your own party]] or healing the opponent. It is uncurable in battle and can only be cured by visiting a healer: it's a huge pain when facing the ramblin' mushroom enemies, and an even bigger pain when this attack turns what should be an easy fight against Shrooom! into an aggravating LuckBasedMission.
** Made even worse when [[spoiler:Ness's Nightmare]] uses it. If Ness has a Night, Sea, or [[RandomDrop Star]] Pendant, it'll just waste a turn. If you gave that to a weaker party member, then you'll be up against an attack with a good chance of either being a one-shot kill, paralysis, or confusion. Against a DuelBoss, that's a very bad thing.
** The preferred attack of a few {{Metal Slime}}s from both games [[spoiler:(Criminal Caterpillar and Master Criminal Worm from VideoGame/EarthBound, and the Beanling and Black Beanling from ''VideoGame/{{Mother 3}}'')]] is a low-level PK Fire, which hits your entire party for massive damage the first time you can possibly fight them.
** There are a lot of attacks in VideoGame/{{Mother 1}} that you will hate. Dehydration attacks, which lower your offense ''and'' defense at once, are nasty, as are last shot and PK Beam Gamma attacks which can instantly kill someone. Was it mentioned that you have to ''go back to town'' to revive a party member? And that the instant-kill attacks [[TotalPartyKill can be used by enemies]] ''before'' [[TotalPartyKill you get your second party member]]?
** The Clumsy Robot will waste most of its turns being clumsy. However, it can "fire a missile, making itself dizzy" for devastating damage, and eat a bologne sandwich to ''fully heal itself''. Both [[LuckBasedMission totally at random]]. [[spoiler:Actually, the sandwich is [[TheComputerIsALyingBastard a lie]] -- it makes the "HP recovery" noise and says "The Clumsy Robot's HP was maxed out", but it really does nothing at all. You'd need to hack the game to realize this, though.]]
* ''VideoGame/SeraphicBlue''
** [[https://www.youtube.com/watch?v=J2TTIORKjdU#t=11m24s Void Finality]]. Will outright kill the party if there are no elements on the field, a later boss uses this as well.
** [[https://www.youtube.com/watch?v=qYyoQx-KCu0#t=6m32s Finishing Killer Wave]]. This will deal damage possibly beyond the HP Cap.
* In ''VideoGame/MegaManXCommandMission'', Ninetails has an attack called Nine Fragments. It deals out a fixed 999 damage nine times. It is very hard to survive this (unless you're [[OneWingedAngel Ultimate Armor X, Absolute Zero]] or Stealth Mode Axl), and it rarely misses.
** You can't mention the Tail clan without talking about Annihilator Hadoken, which deals an insanely high amount of damage (sometimes reaching into the tens of thousands). Also, if it doesn't deal enough damage to instantly kill a party member, it has a high chance of inflicting Crash (at least while fighting Ninetails), which means that they'll still die.
** Epsilon has Meta Crash. It's an HPToOne attack that never misses (unless it targets Stealth Mode Axl). Epsilon ''will'' open the fight with this move, and he spams it after he enters his [[OneWingedAngel Eject form]]. He likes to follow that up with Nova Thunder, which deals immense Electric damage to everybody.
** Silver Horn's Liquid Coating doesn't do any damage, but it is a ''very'' irritating move. After using it, his defenses skyrocket, and he has a chance to arbitrarily guard any attack, so even Thunder - his weakness, what he's ''supposed to take more damage from'' - does minimal damage to him when he blocks. It also allows him to use Pressure Abyss, an Ice attack that is ''always'' a Critical Hit and, unlike most critical hit attacks up to that point, doesn't have any accuracy reduction.
** Atomic Fall, used by the Meltdown. If you can't kill it before it takes three turns, you're looking at a suicide attack that does high 4-digit damage to your entire party.
** The combo of Break Shield and Double Iron used by the Einhammers in Chapter 2. If the Einhammer is the last enemy alive, it sacrifices its defensive stats and from then on will ''only'' use Double Iron, an attack that takes off about 25% of X's health in one strike. The Zwei Hammers later in the game can use this same combo, but it's worse the first time around because at that point X is the only party member you have, whereas later on you have a full party to mitigate the damage of Double Iron.
* ''Franchise/MegaMan'':
** Bass from ''VideoGame/MegaManBattleNetwork 4'' and onwards gets his Buster Rake upgraded. Instead of shooting rolling shiny balls down the rows, this one actually rakes your side of the field several times, is insanely hard to dodge, and the faster he gets, the harder it is to dodge, all the way up to being completely undodgeable. Sure, a single Panel Grab chip will eliminate this, but few people actually bother with it. And in his final forms, every hit deals over a hundred damage, which piles up fast. No matter how high your HP counter is, it's all reserved to tank Buster Rake. He also LOVES to finish off low HP with this. In Battle Network 6, this attack gets buffed even further as it no longer triggers MercyInvincibility.
** Shadowman in ''Battle Network 2'' has a ''nasty'' habit of unleashing Muramasa on the player, an attack that deals damage equal to the amount of lost HP. He only uses it when at [[DesperationAttack low health]] with little warning, resulting in a nasty OneHitKill since it deals over 1000 damage this way.
** In ''Battle Network 5'', Shademan's attack in Liberations has practically infinite range; it can hit anyone next to a Dark Panel. It doesn't matter if he's still within locked panels or if you're on the opposite side of the map, ''he can still hit you''.
** Dark Cloud, a field attacked used by Cloudman during a Liberation Mission. The damage it does isn't so bad, but it paralyzes anyone in the attack's range, meaning that you have to wait a phase until they can move again. God help you if you tried to rush Cloudman with all your Navis.
** Rewinding to ''Battle Network 3'', there's Kingman's Plan B. He uses an Area Grab to reduce your running room, moves his Pawns as close to you as possible, and summons a Knight in your side of the field. Let him live long enough, and he'll do it again, this time using only one Pawn and ''two Knights'', again in your field.
** Gutsman in ''Battle Network 3'' is a tricky step-up from his battles in the previous 2 games, but if left at low HP for too long, he uses his own [[LimitBreak Program Advance]]. For several seconds, he turns invincible and begins launching several {{Rocket Punch}}es at you, each one not triggering MercyInvincibility, and made harder to dodge if he destroyed your terrain moments before. You have to wait this out, which more or less destroys your S-Rank if you ever see him use this attack.
* Players of ''VideoGame/YggdraUnion'' often cringe when the word 'Genocide' is mentioned. It's the signature move of ThatOneBoss Gulcasa which kills off his allies, giving him an exponential boost in power for every unit killed. To make matters worse, this move shatters your meter, preventing you from using any cards to defend yourself with. Finally, if he manages to take out all your characters with this move during a skirmish, your morale takes quite a plunge. And you have to face this guy quite a few times. It's possible to get a character that is effectively immune to Genocide, but the route split happens ''before'' you first encounter Gulcasa.
** Players of ''VideoGame/BlazeUnion'' may cringe when the word 'Jihad'[[note]]English-speakers that played Yggdra Union may call it Crusade instead[[/note]] is mentioned. It's the signature move of Ordene, which immediately causes him to win if he is alone and at MAX Rage Rate. Oh, and you can't block it with Shield Barrier. Good luck with that. [[spoiler:There's a way around it; he won't attack Aegina with it.]]
** BonusBoss #367's Judgment Zero. In her first form it's barely worth mentioning, but in her second form it is practically guaranteed to do Overkill damage, which is an instant loss for you. Like Jihad, it is unblockable and non-elemental, so if she gets it off you ''will'' die. It's a lot more manageable in Blaze and Gloria, where it will only deal Overkill damage if Alanjame or Gariored is alone.
** Gloria Union has Megiddo. It's basically Crusade with a smaller Morale damage bonus, but its user doesn't have to be alone. Once again, it's non-elemental, and Shield Barrier and the new anti-Skill skill Magic Shield do nothing against it.
* ''VideoGame/CityOfHeroes'':
** Many players have learned to fear Ghost Widow. Her darkness based powers are tough, but manageable. Where she really hits you hard is her signature attack ''Soul Storm'', which is a magnitude ''100'' hold that deals continuous damage for several seconds. The average magnitude of a hold (including the player version of Soul Storm) is ''3''. Any character hit with this has a very high chance of dying.
** A close follow up (also from Ghost Widow, though it's available to custom [=AVs=] as well) is Dark Regeneration. Dark Regeneration is a mild [=AoE=] attack that grants hitpoints depending on how many foes are successfully hit. On a heavily Melee oriented party, this is bad. On a party with one or more Masterminds, this is ''very'' bad. Thug and Demon Summoning Masterminds should be particularly wary, as their signature powers (Gang War and Hell on Earth, respectively) amount to what is basically a full heal if used against a Dark Armor wielding Archvillain.
** The Dilemma Diabolique trial had several attacks. The Sentinel of Mot had a (thankfully optional) power that created a difficult to see white circle around him. For every person within this circle, it would rapidly regenerate hit points.
** The Underground trial had several instances of annoying. The War Walkers had targeted abilities that grew in power depending on how many people surrounded the marked player. Don't notice and forget to run? Total wipe. And this part is an EscortMission. Thankfully, most groups left the NPC upstairs. What was even more annoying was the timed battle against the Avatar of Hamidon, which featured an automatic Confuse effect that required ''multiple'' applications of Status resist powers to avoid. If someone didn't notice the "confused" tag on their status bar, they could end up murdering the entire raid, or worse: HEALING THE BOSS.
* Thresher maws in ''VideoGame/MassEffect1'' continually burrow into the ground and reappear somewhere else. That "somewhere else" can be ''directly under you.'' Instant game over. That isn't even getting into its ''actual'' attack, spitting out acid which completely ignores your shields and take off more than half of the [[CoolTank Mako's]] hit points (if you're fighting on foot, the acid attack is very likely to insta-kill). The general strategy people recommend for thresher maws is "run the hell away."
** Biotic enemies love to spam an ability that knocks Shepard down, leaving him/her completely helpless. Fighting against multiple biotics means that you can be stuck to the floor for quite a while, watching your health whittle away without being able to do anything about it (even ''pause the game'').
** The rocket drones in the Luna base frequently fire extremely powerful rockets. They're almost guaranteed to be a OneHitKill unless you have high-level Immunity or very high shields.
* In ''VideoGame/MassEffect2'' there are a ''lot'' more examples of this trope. There are the [[DemonicSpiders Scions]], whose Shockwaves tear your shields to pieces and ignore cover. There are the [[ThatOneBoss Praetorians]], whose Death Choir attack decimates anyone within blast range and fully recharges their Barrier. There's the Oculi, whose energy beams stagger you and deal massive damage. There's [[PeoplePuppets Harbinger himself]], who's fond of using a Singularity attack that knocks you out of cover so he can bombard you with Warp blasts.
* In ''VideoGame/MassEffect3'', Banshees have a homing Warp attack that inflicts lingering damage, a Nova-like attack that strips shields but is unlikely to kill, and a claw swipe. These are all annoying, but manageable. They also have a OneHitKill [[ImpaledWithExtremePrejudice melee attack]], coupled with a [[TeleportSpam generous]] definition of "melee." Other enemies, like Phantoms, Brutes, and Atlas mechs, have instant-kill attacks, but they can only use theirs as a follow-up to a regular melee attack, while the Banshee can grab you the moment you enter its InstantDeathRadius.
* It's not unheard of in VideoGame/WorldOfWarcraft, either. Deathbringer Saurfang, for example, has an ability called "Mark of the Fallen Champion". Players marked by this ability will take massive damage for the rest of the fight, and if they are killed, he will heal himself for a significant amount. You basically just have to [[LuckBasedMission pray]] he doesn't target a SquishyWizard, or you're screwed.
** The bosses of Mount Hyjal seem to have this fairly often. Rage Winterchill, the firt boss, has a Death and Decay that does 15% of each victim's ''maximum'' health per tick. Azgalor has an attack that targets a player every 45 seconds and kills them after a 20 second debuff expires. Archimonde can fling players into the air with Air Burst, and they must know how to use the Tears of the Goddess correctly, or they will fall to their deaths.
*** Because of multiple That One Attacks coupled with his status as ThatOneBoss, Archimonde was considered unfarmable by some servers, even after he was nerfed for ''Wrath of the Lich King''.
** Toward the end of Wrath, if you mentioned the word "Defile" in trade chat, everyone knew what you were talking about. To those not in the know, Defile is an area of effect attack used by the Lich King. He frequently casts it beneath a random player, and its damage ''and size'' increase every time someone stands in it even for one tick. If your 25 player raid group mismanages this ability? [[TotalPartyKill You're dead]]. To make matters worse, he has ''another'' attack that is handled by ''stacking close together'', and since both attacks are on a slightly different timer, they occasionally come out back-to-back. Defile is the reason that, even at the end of the next expansion, when a single character has ten times more health and can output more damage than an entire raid party used to be able to, it still takes a coordinated effort to defeat the Lich King.
** Even going as far back as classic, [[EldritchAbomination C'thun]] had his infamous Eye Beam attack, which would blast a player for respectable damage before bouncing to another, ''its damage doubling each time''. Many stories were recorded about entire 40 man raid groups entering the room at once and getting slammed by this, the very last victims suffering hits in the ''hundreds of millions''. This attack may qualify in-universe for Memetic Badass status, to the point where people have sat down and thought up strategies to maximize its damage, such as taking 40 hunters with 40 pets and having them drop 40 Snake Traps.
** Garrosh Hellscream has Touch of Y'Shaarj, a MindControl effect that he puts on certain players. While afflicted players can be broken out after taking enough damage, they will mainly attempt to put the mind control on other members of the party, and if they get off a cast, the situation will spiral out of control. Once Garrosh gets enough energy, it gets Empowered, resulting in the mind-controlled players having more health and becoming immune to stuns, making it harder to interrupt or free them.
** On Heroic, Wavebinder Kardris of the Kor'kron Dark Shaman encounter uses Iron Prison, an attack that [[OneHitKill does 100% of your maximum health in damage]]. You can only survive it by being topped off and using a defensive cooldown, while also avoiding all the rest of the raid-wide damage.
** While the new version of Karazahn is meant to be brutal from start to finish, Attumen the Huntsman in particular has inspired more healer rage on the forums than all the other bosses combined. Why? A fun little mechanic called "Intangible Presence." It places a ghost on one member of the party, which deals heavy damage over time to everyone. If the healer doesn't dispel it quickly, the party will probably wipe. Every time the healer dispels the wrong person, however, they explode, dealing about a quarter of a typical DPS or healer's health to everyone. The cooldown on dispels also means that cleansing the wrong character guarantees another 8 seconds of the DoT, meaning the party will probably wipe. Of course, the "obey the mechanic or die" check is pretty standard for high-end dungeons and raids. The real problem is how difficult it is to see the ghost which is, well, rather intangible. This problem is only compounded with certain specs that have graphical effects that make it more difficult to see, like shadow priest and bear druid, to say nothing of certain trinkets whose effects actually look a whole lot like the ghost.
* In ''VideoGame/TheLastRemnant'', certain enemies have an attack called Curse which, when your party is afflicted by it, has a 50% chance of killing you instantly. While you can also give the status effect to enemies, [[TheComputerIsACheatingBastard guess which one of you will die from it.]]
* Three bosses in ''VideoGame/PuzzleQuest 2'' have literal OneHitKO moves:
** The final boss has "Subjugation", which will cause your character to surrender the battle, no matter how many hit points either of you have left.
** BonusBoss The Yeti has "Crushing Blow", which does 999 damage (which is about five times the HP you'll probably have when you first confront him). The regular boss, Iron Golem, also has it, but doesn't have The Yeti's near-broken red mana gain, so if the Golem gets enough to cast, you were probably just a victim of bad luck.
* ''Franchise/DotHack'' has several. The first game has Skeith's "Judgment", which hits the whole party, is impossible to avoid or block, and hits for roughly 70% of your health. Then there's Macha's attack which inflicts Charm on the whole party... which means they beat each other up until it wears off, and you can't heal it because it hits the ''entire party''. Then there's Tarvos's Cursed Death Play, which only targets one character, but cannot be avoided and is a guarenteed OneHitKO. All of the Phase bosses are also capable of Data Drain, which only targets one party member but destroys their HP and infects a number of status infections. And it can be spammed.
** In ''VideoGame/DotHackGU'', there's Azure Kite's "Azure Tiger Claws". It is possible to block this, but it requires some very tricky timing: the attack is timed so that if you do a full combo (which is what most players instinctively do), it will hit you during the lag between attacks. Later, in Redemption, there's "Chaos Gehenna", used by Cubia Beta. Once his HP hits around 20-30%, he simply spews a long stream of Gomoras at you. It's next to impossible to dodge, and harder to destroy all of them without taking damage. Also, since this is an Avatar Battle you cannot heal, and if you lose you must restart the battle from the Cubia Alpha phase. Chaos Gehenna is so bad that it can arguably make Cubia into ThatOneBoss.
* Orjugan, ThatOneBoss of ''VideoGame/YsVITheArkOfNapishtim'', has a deadly WaveMotionGun style laser blast, which is difficult to dodge without also getting hit by his CombatTentacles, which [[OneHitKill can kill you in one hit]] on Hard and Nightmare difficulties.
* There are more than one here, but the Megiddo technique from ''VideoGame/PhantasyStarIV'' deserves notice. It was a staple attack-all ever since the second game, and suddenly, the final boss has it like your main character. (In addition to sucking up souls or whatever before performing.) Absolutely devastating when the boss decides to remove your buffs, and man can it spam like there's no tomorrow.
* ''VideoGame/BreathOfFireDragonQuarter'' has Malefactor, used by [[spoiler:Dragonized Bosch]]. It afflicts the party with every status in the game. So unless you're going to unleash everything with Ryu's powers, you're gonna want to have even one person with immunity to bail the others out (if not more).
* Late in ''VideoGame/TrialsOfMana'', many level 3 techs when used by the enemies, such as Split-Image Slice or Vacuum Sword, will hurt everyone in the party for around ''80-90%'' of their max HP. These attacks can take a fully healed party to critical, or a party in decent shape to [[TotalPartyKill dead]]. If two of these are used on you in a row, [[{{Unwinnable}} you're just screwed]]. And keep in mind, these are attacks done by ''[[{{Mook}} normal enemies]]''.

* The spell Abi-Dalzim's Horrid Wilting in ''VideoGame/BaldursGateII''. On paper, it does 1-8 damage per level of the caster, half on a successful save...but a mage has to be level 15 to know it, meaning an awful lot of damage is being thrown around. This is somewhat unfair when you are a SquishyWizard with less than 40 health and oh sorry just failed your saving throw, time to reload. Especially since unless you were a ''very'' dedicated grinder you are still two levels away from being able to cast it yourself (which is, admittedly, very therapeutic).
* ''VideoGame/NeverwinterNights'' has Harm. A ''very'' distinct pillar of red light slamming down upon you and reducing you to 1 HP. If you have other enemies nearby or are in some kind of damaging effect, prepare to die.
* ''VideoGame/MegaManStarForce'':
** Apollo Flame in the second and third game has an attack where he drops a miniature sun on Mega Man's side of the field. This attack comes out very quickly, it can't be dodged or blocked (unless you knock him out of it first), and it cracks your panels. It also hits multiple times, so not even a Barrier can save you.
** Sirius, from the third game, has Satellite Blazer, which hits and ''breaks'' every tile of the field and can't be blocked (or dodged for that matter, unless you have Air Shoes). He also has a move where he detaches his wings and starts [[BeamSpam blasting the field with elemental lasers]] -- it can't be blocked, and can easily knock you out of an elemental Noise form if you're not careful.
* ''VideoGame/MinecraftDungeons'': [[spoiler:The laser attack from Heart of Ender. This attack can instantly kill you within less than 5 seconds if you don't avoid it properly, and even touching it for a little bit can take half of your health. Unfortunately, the boss also spams fire all over the place, making completely avoiding it near impossible. Luckily, the laser can be blocked through the Totem of Shielding.]]
* The final boss of ''VideoGame/SkiesOfArcadia'' brings us the Silver Nightmare attack, where he possesses one of your party members and forces them to use one of their special moves against one of their own allies. It has priority over EVERYTHING, even defensive moves like Justice Shield, and is the only damaging move in the game that has this high a priority. And the possessed party member loses their action for that turn, and quite often you will see him turning Vyse's Pirates' Wrath into a OneHitKill of your SquishyWizard, making that two actions in one turn you just lost, and often more because you get to watch your characters uselessly start using their shield moves. Have fun catching back up with the battle flow!
** As far as ship battles are concerned, there's Bluheim's Blue Winds attack. While technically by itself it does the least damage out of Bluheim's attacks, it causes the ''entire next round'' to be filled with nothing but tiles giving an advantage to Bluheim, which is just as painful as it sounds. The only other attack in the game that does this (Auriga's Hull Ram) is easily avoidable by casting Quika; the best you can do with Blue Winds is use the Guard command...in which case the next round is instead filled with tiles that give Blueheim ''slightly less'' of an advantage.
* Flash game ''VideoGame/{{Sonny}}'' has Baron Brixius' Tick Tock debuff, which deals damage equal to 10% of the victim's maximum HP... and continues to do this for 10 turns. It also cuts any healing they receive in half, can be cast on multiple characters at once, and can't be removed by status-removing spells. Note that this game has no multi-target healing and no way to revive dead allies. Note also that Baron Brixius would be a MarathonBoss ''without'' this attack. With it, he becomes ThatOneBoss. The only saving grace is he likes to use it on ''himself'' if you last long enough.
* The ''VideoGame/EtrianOdyssey'' games are liberally sprinkled with these, as you'd expect from a game this NintendoHard. In general, almost no enemy's basic attack will seriously endanger anyone so long as you have a healer, but even common enemies have abilities such as giving the entire party status effects or doing enough damage to one-or-two shot even the hardiest Protector. The fact that StatusEffects can entirely ''prevent'' these moves from being performed is what keeps them from being {{Useless Useful Spell}}s.
** Shin fron ''The Drowned City'' has a nasty one called 'Demon's Kiss'. It hits various random party members multiple (from two to ''nine'') times, for various amounts of damage, and then heals the boss.
** Enemy {{Combination Attack}}s (signaled by the text "(enemy) stands ready!") can be stopped by killing or disabling the enemy who will perform the attack, but failure to do so and they will do something seriously nasty to your party, such as status effects to all units or just killing at least half of them with massive damage.
* VideoGame/TricksterOnline brings us Suicide, Banish, and Berserker:
** Suicide is exactly that - a monster that is threatened will explode, taking you with it. Of course, there are some cases where a monster will Suicide while not actually having taken damage already...
** Banish is the bane of Freebie Newbies - If you're inside the banish ring after three seconds, you get instantly teleported to The Hub. Most bosses have this as an anti-Tank measure, and one set of boss trials have an entire room dedicated to not getting hit by Banish (while still getting hit by skills that keep you from moving at all)
** Berserker significantly increases the user's attack power (AP). When a player uses Berserker, they also lose control of their character until the effect ends, and the game selects nearby enemies at random (read: if you use Berserker while in the middle of a crowd, you will do nothing for the first five seconds), it blocks you from using skills, it reduces your health as long as it is active, it lasts for 20 seconds, and you can only start it once every 30 seconds. When a monster uses Berserker, it lasts for 30 seconds, the cooldown is 20 seconds, they can use skills, and they start moving faster. Heaven help you if you come across a monster with both Berserker and Guard Break.
* In ''VideoGame/XenobladeChronicles1'':
** Jade Face/[[spoiler:Gadolt]]'s Laser Bullet does an absolutely massive amount of ether damage that can easily OHKO party members with lower max HP values, has a huge hit radius that makes it almost guaranteed to hit everybody, and leaves them dazed if they do survive. If you lack the few means of mitigating ether damage effectively and/or aren't of a significantly higher level then him, it can make winning extremely difficult.
*** Another attack that is very similar are the Dragon's fire breath attacks where they fly out of attack range and do a lot of damage as well as Blaze. However [[spoiler:Avalanche Abaasy's is far worse then the other's. It also inflicts Paralysis and because of Avalanche Abaasy's huge 3,200 Ether power this does even more damage for the entire party if it connects]]. What will kill you in this fight is most likely the Blaze damage or the attack itself if you don't have a Level 10 Monado Armour which is almost needed for the [[BonusBoss Super bosses.]]
** There's also Titan Stamp from [[spoiler:Magestic Modred and Mischevious Naberius]]. This attack hits all of your party with a large radius and does a very large amount of damage having an Arts Multiplier of 4.0. Not only that but Monado Speed only works on one person and you won't likely have [[spoiler:Monado Armour]] by then which works on everyone.
** [[spoiler:Avalanche Abaasy]] also has its Talent Art which can do lots of damage due to how much high its Level is and its Art Multiplier is a 5.5. Just like Titan Stamp it has a large attack radius and hits all of your party members. It can even instantly kill at times if it gets the max multiplier. Thankfully you should have a Monado Shield X at this point.
** [[spoiler:Mysterious Telethia]] has two Talent Arts, both of which are extremely dangerous, being Supernova VIII and Ultimate Cannon IX. Both of these are That One Attack if they aren't blocked by Monado Shield, but the biggest threat is Supernova. It does an insane amount of damage and it's 4 blasts of extremely powerful Ether. This does over 7,000 damage and if you don't have Monado Shield VIII at this point you will be taking a lot of damage and potentially a OneHitKill if you're using someone who doesn't have a lot of HP.
* ''VideoGame/XenobladeChroniclesX''
** Apocalypse Roar from [[spoiler:Chimera Lao]] ''depletes your Skell's fuel meter'' if you're in one, essentially forcing you to fight him on foot.
** Terrible Eye from [[spoiler:Lugalbanda, the Wanderer-King]] inflicts the Control status on your entire party, forcing them to do absolutely nothing except awkwardly strafe for several seconds. No cancelling out of fight mode, no attacking, no escaping, ''nothing''. It also can hit through [[GameBreaker Decoy]].
** Any attack that can topple you, because of how long it takes to get back up even if it's just Topple I. It's even more so when in a Skell, as the topple period lasts much longer.
** Rexoskell's Serpent Beam hits 7-8 times for up to 1,000 damage a hit, and can shred away Decoy like nothing.
* ''VideoGame/EpicBattleFantasy''
** In ''Epic Battle Fantasy III'', there's Doomsday, used by [[BossInMookClothing Cosmic Monolith]]. It deals huge dark-elemental damage to everything on the field - but Cosmic Monolith actually absorbs dark, meaning it can bring your whole party to near death while healing itself. The attack is used every three turns, so if you can't outdamage the healing (taking into account that you also have to recover your health in meantime), you're screwed. An optional fight with two Cosmic Monoliths is actually harder than the FinalBoss.
** ''Epic Battle Fantasy 4'' has a few, but one of the worst is used by the Clay Idols (which are otherwise a pushover mook). They have an attack that drains a character's MP. What makes it so nasty is that the amount it drains is completely ridiculous; a single hit can steal roughly 90% of a character's MP total, essentially forcing that character into backup so that their MP can (slowly) regenerate and making them practically useless for the rest of the battle, or else forcing you to run away and restore your MP out of battle. For this reason, it's generally recommended to take out Clay Idols on sight, before even buffing (which you would normally spend most of the first turn doing).
** [[EvilCounterpart Dark Lance]] is generally considered the toughest BonusBoss in ''IV'' due to one attack: Unload. In the player's hands, Unload is nothing special, since it's a physical attack on a mainly magical-attacking character, and it debuffs the user's attack afterwards to prevent it from being even remotely spammable. In the enemy's hands, though? Not only does Dark Lance have a sky-high physical attack, [[MyRulesAreNotYourRules Unload does ''nothing'' to his attack stat]] - he can, and ''will'', use it multiple rounds in a row. And it can hit multiple targets in a single action, [[TheComputerIsACheatingBastard which your version of Unload cannot do.]] Like your version, it hits 6 times, and if Dark Lance has previously buffed his Attack stat (and bear in mind that Dark Lance is ''resistant to dispel''), it can easily [=2HKO=] or even [[OneHitKill OHKO]] with just a single one of those shots.
* ''VideoGame/DarkSouls'' has quite a few. Chaos Witch Quelaag has a devastating area of effect explosion attack; even with high fire resistance, it's likely to stagger you and take off quite a chunk of health. It's telegraphed well in advance[[note]]When Quelaag hugs the spider, ''run''[[/note]], but if you don't get your shield up or get away, you'll get your face blasted off.
** Grappling attacks are unblockable and will usually take off at least three quarters of your health bar every time you're grabbed. Sure, they're telegraphed, but if you're focusing on finishing off another monster or overestimate your dodging ability, it's very easy to get an amateur tracheotomy courtesy of an Infested Ghoul's teeth, or pecked to death by a Crow Demon, or chewed on by the Gaping Dragon, [[TheManyDeathsOfYou or stabbed through the chest by a Wailing Ghost, or smashed into the ground by the Iron Golem]]...
** The Basilisk's attack, which spews a gray cloud of fog that causes curse. Curse is easily the deadliest status ailment in the game, and extremely hard to remove.
** The basic Hollow, the weakest enemy in the game, has an attack where it frantically swings its weapon while dashing forward. Normally even this attack isn't all that strong... unless that Hollow happens to be holding a torch instead of a broken sword, in which case the attack can break pretty much any amount of [[ImmuneToFlinching Poise]] and evaporate your health bar as you are helplessly stunlocked.
* ''VideoGame/DarkSoulsIII'' is no slouch in this department either.
** Holy Knight Hodrick's ripostes. When Hodrick invades you, he's a faintly absurd parry god who can block your attack, then one-shot you with a riposte to the face.
** Aldrich, Devourer of Gods, has [[spoiler:Gwyndolin's]] magic arrow bombardment. In his first phase, it draws a straight line that is fairly easy to avoid. In his second, it ''hunts you down'', can stunlock you to death, and lasts for fifteen seconds, which, in the heat of battle, can feel like a week - especially since he doesn't have to do anything to sustain it once it's going, and thus can cast more spells or hit you in the face.
** The King of the Storm/Nameless King fight is just plain annoying, but the blast attacks are the worst thing about its first phase: the downwards fire breath creates a spreading, fast-growing pulse of fire about the size of Kansas, while the lightning spear shockwave is a devastating blast that's hard to dodge accurately.
** The Consumed King's charge has a messy hitbox and a wind-up time that is only perceptible to mayflies.
** In the Twin Princes fight, there's Lorian's teleporting dive attack, which has a wind-up of about a nanosecond. Overextend even a little and he blinks out of existence, then reappears right above you and slams his sword into the top of your head.
** The FinalBoss has a bunch of fun attacks. In his first phase, he has some very powerful spells in his sorcery mode, including the ability to put up a proximity-activated soulmass ''while'' firing a WaveMotionGun that will disintegrate you if you get caught in the blast. In his second, he has a devastating multi-hit combo that's then followed up with a hugely powerful AOE. Get caught by the first and the second will vaporise you.
** Sword-wielding Ringed Knights have a five-hit sequence that is almost impossible to interrupt. When you see one's sword catch fire, either beat him down before he starts the attack, or ''get away''.
** Judicator Giants can summon multiple annoying ghosts to attack you, but if the Ruin archers are turning up, ''hide behind something''. They put out agonising volleys of staggered shots that can stunlock you into oblivion.
** BonusBoss Darkeater Midir from the ''Ringed City'' DLC gets you coming ''and'' going. Sticking close to him in order to hit the head? Get an inch too far underneath and he'll use a downward fire breath attack, that covers a ridiculous amount of ground. Standing back to punish him with arrows or ranged lightning miracles? His Godzilla laser breath draws a line in the ground that deals massive damage...then he whips it around sideways, also dealing massive damage and moving insanely quickly, so you get disintegrated before you can do anything.
* The Procrastination Giant in ''VideoGame/KingdomOfLoathing'' will sometimes counter melee attacks by sneezing on you. This causes the status effect "Cunctitus", which makes you procrastinate. Which is to say, a good 80% of the time you try to make a move in combat, you get the message "You decide to [perform this action] later." This is usually followed by the message, "You lose."
** The Protagonist from the preceding area ([[Franchise/FinalFantasy Penultimate Fantasy Airship]]) can cause the [[LaserGuidedAmnesia "Temporary Amnesia"]] effect, which disables ''all'' your skills. Mildly annoying if you're a Muscle or Moxie class which can just spam their default attack to win, deadly if you're a [[SquishyWizard Mysticality class]] who relies on spells to fight.
** To fully qualify, those (along with a high chance of getting poisoned in multiple ways from multiple sources during the next major quest) are the most memorable attacks any non-boss will use against a brand new player, and are nastier than any boss attack up to that point as well. They fit this page because ''every'' player at some point was a brand new player and very few will have been ready with appropriate counters to all of those. The game universe as a whole features numerous examples of devastating and truly unfair enemy attacks, but the nature of the game is such that experienced players usually have so many effective fighting styles and metaphorical "I win buttons" ready that it's hard to single anything out as a threat to ''everyone''.
* ''Franchise/TheElderScrolls'':
** ''[[VideoGame/TheElderScrollsIIIMorrowind Morrowind]]'': Greater Bonewalkers have an ''infuriating'' "damage attribute" spell. Note that says "damage" and not "drain." "Drained" attributes will go back to normal once the spell wears off. "Damaged" attributes will stick with you until you heal them with a temple blessing or potion. It's incredibly frustrating to encounter a greater bonewalker halfway through a difficult dungeon only to have him damage your strength attribute so much that you are forced to dump half your inventory (strength determines how much you can carry) in order to flee back to civilization to heal.
** ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'': High level draugr are capable of using the same dragon shouts as you, including the "Disarm" shout. Any weapon you are holding will fly out of your hand and across the room. This alone is annoying, but reasonable. It becomes unreasonable when your weapon occasionally flies into unreachable places, such as ''through the floor or wall.''
* Terracor's curl, the possession attack of the two Shade bosses (which, in addition, can potentially kill any possessed party member so the bosses can recover part of its energy) and Mystic Spider's swallowing attack in ''VideoGame/TheLastStory''.
* PSI Bitchkill in ''VideoGame/TheHalloweenHack'', which can kill your entire party in one hit. Thankfully, it can be reflected.
* Hit-all attacks in ''VideoGame/TheDenpaMen'' are oftentimes devastating, but among the most dangerous is the "Extended its roots" attack utilized by a great number of plant-like enemies. It smashes the entire party for a large amount of Earth-type damage. Even orange, Earth-type Denpa Men and bulky tanks will probably be left with little health after just one, and you can almost assuredly kiss your ability-users goodbye when it hits. The [[BossInMookClothing Hydraplants]] can attack ''twice'' with it in one turn, almost assuredly leading to a TotalPartyKill.
* In ''VideoGame/LilMonster'', the Meteor Drive attack is the most powerful attack in the game, and the player cannot obtain it until right before the FinalBoss. But even early-level enemies, and those in the earlier tournaments, can use it. Even when used by the weakest monster in the game, it still does over 100 damage.
* [[spoiler:Demon Lord]] Trevor in ''VideoGame/ExitFate'' has Annihilation Ray, which does a fixed 5000 damage to a character. That is much more HP than any of your characters can realistically have, and it can't be weakened with Shield. A later boss, Mephisto, brings it back and it's just as devastating.
* ''VideoGame/LufiaAndTheFortressOfDoom'':
** The game has archer enemies that come in groups of three to four and love to spam Hi Arrows, an attack item that hits everyone in your party for rather hefty damage. An entire group of archers using Hi Arrows will easily knock out Lufia and leave the Hero and Aguro on the verge of falling.
** The final bosses, Daos and [[spoiler:Guard Daos]], have Amnesia and Figual. Both have a high chance of inflicting paralysis or confusion respectively on your entire party. Amnesia is far more dangerous on its own, but because [[spoiler:Guard Daos]]'s moveset was reduced to two attacks in the western releases, Figual gets spammed non-stop during the final fight.
* ''VideoGame/LufiaIIRiseOfTheSinistrals'':
** The game has Mortal Blow, which has a high chance of instant death. What makes it That One Attack is that the enemies that use it, the Ninja and [[BlindIdiotTranslation Asashin]], are ''insanely'' fast both out-of and in-battle, meaning it's very difficult to avoid.
** The Gold Dragons near the end of the [[BonusDungeon Ancient Cave]] attack ''three times per turn''. One of their attacks is Stardust Blow, an extremely powerful [=fire/holy=] attack that hits everyone in the party. If a Gold Dragon uses Stardust Blow twice? Everyone in your party is dead, with the possible exception of [[SuperToughness Dekar]]. Uses Stardust Blow three times, or ends with [[HolyHandGrenade Fry]]? Nothing's going to save you then.
* ''VideoGame/LufiaTheLegendReturns'':
** Spiritual Force of Chaos, Amon's signature attack which can inflict confusion on every party member. Normally, only three members (of up to nine) can attack per turn. Confused members aren't under this restriction. [[spoiler:Oh, and Guard Daos has this attack too.]]
** There's also Destroy, the multi-target instant-death spell. Under normal circumstances, it ''might'' knock off one or two members (and fallen members revive after battle anyway). But after [[spoiler:the party gets drugged by Leydeck]], you're reduced to ''two'' members, at which point Destroy becomes horrifyingly likely to cause a TotalPartyKill.
* Reaper Hit in ''VideoGame/LufiaTheRuinsOfLore'', an attack with a chance of instant death. That is only encountered in the BonusDungeon. That ''only the main character'' can enter (with his {{Mon}}, but WeCannotGoOnWithoutYou applies to human party members).
* ''VideoGame/LufiaCurseOfTheSinistrals'':
** Both forms of [[spoiler:Gades]] have a three-hit combo attack that knocks you down on the first hit, leaving you vulnerable to the rest of the combo. The first form's combo will cleave off more than half of your HP meter with one combo. The second form's combo can kill [[GlassCannon Tia]] from full HP easily.
** The scarecrow enemies' sleep spell. Getting hit by it is nigh-guaranteed sleep, which leaves the character completely immobile and unable to swap out until it wears off or you cure it...perfect for the scarecrows' highly-damaging fireball attack. In the first dungeon you encounter them in, Maxim and Tia ''will'' get killed if they get hit by sleep without anything on hand to cure them.
** The spinning top enemies aren't too tough, and even their spinning attack that stunlocks your character won't do much damage with a bit of buffing. The red variants you encounter in the Ancient Cave do around '''200''' damage a hit even with high DEF, guaranteeing knock-out if you get hit by their spinning attack.
* If you're taking the bad ending path in ''VideoGame/{{Undertale}}'', you'll have to fight [[spoiler:Sans]] at the very end, and his ''opening attack'' is this. If you actually survive it, he'll lampshade it, stating that he had wondered why people don't just use their strongest attack first. And if you have to repeat that battle, they'll sometimes interrupt his own intro speech with the attack, to catch you off guard even if you've memorized the pattern. They also get an attack that is mechanically a copy of the difficult hoverbike sequences from ''VideoGame/{{Battletoads}}''. Finally, there's the last attack: in addition to being significantly faster and more hectic than their opening move, it lasts for a full ''30 seconds''.
* ''VideoGame/LastScenario'':
** The [[WakeUpCallBoss Marid King]] has Freezing Sword, which he can use ''during your turn'' as a counter. It deals a decent chunk of damage which can be mitigated with an accessory that nullifies it, but even with that accessory you can still get Slowed by it, which makes the fight very irritating. The rest of his attacks are water-elemenntal, and there is no way to mitigate that at this point the game.
** Castor has ''Maelstrom'', a single-target attack that deals damage and inflicts slow, berserk, chaos (akin to confusion in other [=RPGs=]) and petrification. If you don't have a way to block at least one of these effects, you'll be spending more of your time recovering from Maelstrom than actually fighting Castor as he pounds you into the floor over and over again.
** [[spoiler:Alexander]] has ''Lionheart'', which deals ludicrously high damage and ''hits twice''. Even if you're somehow able to tank the first hit, the second one will finish off even [[MightyGlacier Matilda]], or if the first hit was enough, it ''targets a second party member''. Basically, unless you've been using lots of Vitality Capsules to jack up your party's defense, it constitutes half of a TotalPartyKill.
* ''VideoGame/TheWorldEndsWithYou'':
** Yodai Higashizawa, the first game's Game Master [[spoiler:(of the first week, that is)]] has his electric orb spam, announced with "I'll char your bones black!" This is his only attack that targets ''both'' Shiki and Neku simultaneously, requiring them to stop attacking entirely and focus exclusively on defense until it's over.
** ''[[VideoGame/NEOTheWorldEndsWithYou NEO]]'' has [[spoiler:Ayano Kamachi]]'s slap attack. One by one, she stuns your party members (most of them -- she doesn't do it to Rindo or [[spoiler:Shoka]]) before walking up to them and delivering an ''extremely'' powerful slap that can drain all your HP if they all connect. It's possible to free your party members by breaking the chains she summons, but if you don't have powerful ranged pins (or if you do but they're on the targets for this attack) you won't make it in time. Even worse, she only uses it at low health ''and'' gets a LastChanceHitPoint that guarantees she's able to do this move, and having to redo the entire fight due to this attack can be very frustrating.
* ''Videogame/SaltAndSanctuary'':
** The Bloodless Prince, a gigantic three-faced golem, is actually relatively easy as long as you stay up close, due to massive telegraphing of his attacks despite their area of effect. Again, if you stay up close. If you don't, the Prince will decide to close the distance by way of flopping onto you from afar, which causes a massive quake that, due to ridiculous, arena-encompassing area of effect, is essentially impossible to properly dodge unless you're at the very edge of the arena.
** The Witch of the Lake, ThatOneBoss extraordinaire, has her infamous "flame machinegun" that sprays ridiculous amounts of fire from her staff into an area in front of her. The only way to avoid this attack is to either be far away so only a few bits reach you, or to be right under her so the fire goes past your head. If you're at medium distance, and don't have an excellent shield up ''that exact second'' you are dead, no questions asked. While her other attacks are horribly damaging you can at least survive them with some last-second dodging, but if you're in the impact zone for this one not even the best roll timing will save you.
** [[spoiler: The Forgotten King, from the Three]], has an untelegraphed and very quick kick that looks more like he's simply stepping on you casually. It's close to impossible to react on time so the only way to avoid it is to be dodging before it starts. It does little damage, but it ''will'' knock you down, which is not a good thing when you're facing three bosses at once (as is this particular fight's case).
* ''VideoGame/JojosBizarreAdventureThe7thStandUser'':
** Several bosses, including the Water Claw and (in the BossRush) Hanged Man can "go for the jugular", which doesn't do much damage but has a very high chance of causing instant death. This is a serious problem in a game where you're limited to two party members for the vast majority of fights, including these two. Tower of Grey (the ''very first boss'') gets a more accurate version of this named Tower Needle, though he doesn't use it in the first fight unless you're on Hard Mode.
** All of the Anubis fights have "I've memorized it!", a stacking general buff. They combine this with Iai Slash, a very strong party attack that just gets even stronger as the fight drags on. Whether you're able to win these fights at all is dependent on how quickly you're able to buff your party before they get too powerful.
* In ''VideoGame/BetrayalAtKrondor'', the spell "Grief of 1000 Nights" freezes a character for a number of rounds. This is nice when used by one of your mages; however, if enemy mages use it on your party it is far deadlier, as when all of your characters are frozen the game treats it as a Game Over, even if their hit points are still high enough to survive more attacks before the spell wears off. It gets worse in combats with multiple enemy mages, especially if your party screws up a surprise attack and goes last, as sometimes you'll get frozen up so quickly you may not even get a turn.
* ''VideoGame/ArmoryAndMachine'':
** This trope is invoked with the various rat enemies and Rat King boss in the Badlands, the second area of the game. All of them have rather weak basic attacks, and they also have one attack that has a slower cast time but deals a ''whopping'' 300 or 400 HP damage at a point where you have 600 max HP ("Bite" for the Sad Rats and Mad Rats, "Gnaw" for the Dust Crawlers, "Radioactive Bite" for the Glowing Rats, and "Royal Decree" for the Rat King), pretty much guaranteeing a defeat if it hits you. The trick here is to use the Stun ability, which causes their prepared attack to fail and do nothing. Out of the four, the Dust Crawler's Gnaw is especially bad, as it has a much shorter casting/interruption time than the rest of the enemies' dangerous moves.
** The Vacuous Bats in the Cliffs area will usually use a move called "Fly", which does nothing. However, their AIRoulette will randomly use "Swift Bite", which deals 300 damage to your 600 HP when you first encounter them. If they use this twice before you can beat them, you're toast. You can use Stun to stop it, but that takes up a precious skill slot and will hamper your potential DPS.
** The Ninja Frogs in the Cliffs are similar to the bats, using several fake-out moves that do nothing, but after their AIRoulette uses "It's Coming", it has a high chance to use "Shuriken" to deal 300 damage, and unlike Swift Bite Shuriken has a far shorter casting time making it harder to anticipate and interrupt. The only good news is that sometimes it might user Honorable Healing instead of Shuriken, which heals you for 100.
** "Chip Swarm" by the Pebble Swarm. It hits for [[DeathOfAThousandCuts very weak damage but is used extremely rapidly]], which will immediately interrupt any of your more powerful attacks that have a cast time, and this also means that it cannot be interrupted since you can only disrupt one of the hits. Furthermore, this attack can last for a huge period of time, eating away at your shields and health. The Rock Golem boss also uses a similar move, but it doesn't last as long as the Pebble Swarm's.
** Of all [[spoiler:the [[FinalBoss Original Machine's]]]] attacks, we have "Target Laser". Its other attacks hit harder at 1000+ damage or so but can be interrupted in the cast period to prevent damage entirely. Target Laser deals only 250 damage but the boss [[SpamAttack uses it 7 times in a row]] followed by an 80 damage shot. This would normally seem easy to chain-interrupt as Target Laser's first cast starts slow, but each subsequent casting time is lowered regardless of cast success. You only have four moves that can reliably interrupt them, and they take 10-20 seconds cooldown. This means that unlike all its other moves, you will not be able to interrupt all of it and will take at least 1-3 hits plus another 80 damage at the end.
* ''VideoGame/ArmoryAndMachine2'':
** The Snake and the [=JrBot=] have "Paralyze", which permanently stuns you until they kill you with their attacks. The good news is that it has a long charge time to interrupt and is a great opportunity for you to use Bomb on them. The Wild Snake's version of Paralyze fortunately only stuns you for 8 seconds, but it's still a good way for it to deal heavy damage on you.
** "Crab Toxin" and "Poison", used by the Giant Crabs and Toxic Slimes respectively in the Wilderness. Unlike the regular Crab's Crab Poison which merely lowers the damage of your next attack by 5, these two inflict an ''actual'' poison status that lasts 30 seconds and lingers even after the battle ends, halves all your damage dealt, and deals 2 damage to you every few seconds which will interrupt your casting time attacks. Players who assume that they can simply take this Poison as lightly as Crab Poison will be in for a ''very'' rude awakening.
** The Zombie's "Bite". It isn't a very painful move but the Zombie can spam it if the AIRoulette chooses to, and if the attack connects (due to overwhelming your interruption move cooldowns) it will heal the Zombie for 50 of its already-high 200 HP, effectively wasting 1/4 of your efforts in killing it.
** The Forest Nymph's "Protect". It has an extremely fast cast time, tends to be used almost every alternate turn, and if not interrupted it will provide a damage shield to the Nymph. Said damage shield makes them regenerate health from Blast- and Explosion- type moves (pretty much your entire arsenal for the first 4 areas of the game) and lasts 10 long seconds, meaning that if they manage to pull this off ''once'', you're as good as dead if you lack any physical or elemental attacks.
** The Angry Orc and the Sleepy Guardian Orc have "Club Smash", which deals a huge 40 damage where you have only 100 max HP. It's the first long-casting attack in both games that ''[[ImmuneToFlinching cannot be interrupted]]''. This enforces you to have both a healing move and a way to increase your dodge or defense, and if it's used multiple times in succession to overrun your Regen use, you're out of luck. It's one of the reasons why the Sleepy Guardian Orc is the [[ThatOneBoss toughest of the five bosses in the Wilderness]].
* ''VideoGame/GranblueFantasy'', having as many raid bosses as it does, has its fair share of these.
** Colossus Omega's Dimensional Cleave, which has a damage output so high that not even Phalanx III is strong enough to stop its target from getting killed, even if you're using a Water team. This attack is what makes this raid a WakeUpCallBoss for some newer players, as mitigating it can be a challenge.
** Conjunction, used by both versions of Grand Order. It's a party-wide HPToOne attack, and on the easier version of the raid, it also ''randomizes the cooldown length'' of all your skills. If it happens to shut you out of your healing skills for several turns... well, hopefully you have a spare Full Elixir to get back into the fight.
** Proto Bahamut (both the regular and Impossible versions) has Skyfall, which deals [[FixedDamageAttack ten million]] dark damage to the entire party. This ''will'' kill you unless you're able to get a full damage cut for the party. And the regular version is guaranteed to use it twice during the fight.
** While the Impossible version of Proto Bahamut isn't guaranteed to use Skyfall, it ''is'' guaranteed to use the way nastier Supernova, which deals 95% of each party member's maximum HP as [[NonElemental plain damage]]. While it does less damage than Skyfall, it is ''much'' harder to guard against, as plain damage ignores most defensive buffs; the only way to survive it is to make sure you're as diligent as possible with healing.
** Any attack that can [[StatusBuffDispel remove all buffs]] from the party can be this depending on what the boss can follow up with, but special mentions go to the following:
*** Luminiera Omega's Blade of Light, which randomly hits for big damage five times, fully dispels the party, and as the cherry on top, it paralyzes a random party member. If you're unlucky, this can come right after Aegis Unmerge, making her attacks much stronger and turning Blade of Light into a TotalPartyKill instead of just a full dispel.
*** Anubis's Ophois, which hits the whole party, removes all buffs, and has a chance to lower multiattack rate and debuff resistance and/or, even worse, inflict Zombie on them. What makes this one so bad is that Anubis is guaranteed to use it at least five times during the fight, and it gets progressively stronger the lower its health gets, to the point of needing some heavy damage cuts to tank it near the end.
*** Europa's Floral Prison doesn't do damage and only dispels one character as opposed to your whole party, but it makes up for this with the two status effects it also inflicts on the unlucky target; Azure Spike and Held Under. The former makes any attacks from the character ''heal Europa'' (and there's no way to stop them from attacking unless a status effect prevents it), while the latter prevents any healing on them, lowers their accuracy, and makes them take heavy damage each turn.
** Avatar has Archenemy, which is Skyfall taken to the extreme -- ''one hundred million'' dark damage to all allies. Fortunately, it only uses it once.
** Lu Woh's Flashpoint Trajectory, which is a TotalPartyKill that also affects the backrow. There are other raids that have attacks like this, but they exist solely to say "you messed up, now do the raid over". Flashpoint Trajectory, meanwhile, is ''a regular move that Lu Woh can use at will'' below 40% health. While it's possible to cancel this move, doing so requires hitting Lu Woh '''99''' times in one turn.
* In ''[[{{VideoGame/LISA}} LISA: The Painful]]'', "Neck Break", "Heart Squeeze", "Fatal Chomp", and "Decapitate". These are the only four moves in the game that can [[{{Permadeath}} permakill]] your party members, even if they're at full health. The worst part is that, while most bosses are obviously capable of using these moves, many random {{Mooks}} are also able to use these to completely wreck your party composition at a moment's notice.
* In ''VideoGame/ShadowHeartsFromTheNewWorld'' both the strongest BonusBoss and FinalBoss have a move called Lost Progress. True to its name, it's a StatusBuffDispel. The problem is that the bosses will use this ''instantly'' when you cast a StatusBuff - they just get a free turn as soon as you use a buff to cast Lost Progress. Because the developers thought that wasn't enough, the bosses then get ''another free turn'' immediately afterwards. You essentially ''cannot use buffs'' against these two bosses as a result.
* The postgame of ''VideoGame/BugFables'' has a fight with [[spoiler: Stratos and Delilah]], the latter of the two able to brandish a [[{{BFG}} bazooka]] and assault your party with a flurry of status-inflicting ammunition. It can hit up to ''12 times'', each hit dealing high damage (especially in hard mode) and guaranteeing a status on a bug unless you time your guards well enough. In addition to being able to take out an entire bug's health pool, it can inflict 2 new status effects that can either prevent item or skill use, and are incurable by most means.
* ''VideoGame/OctopathTraveler'':
** The dragon at the end of H'aanit's Chapter 3 can use Swept Away, removing any one party member from the field for several turns. If it's your main healer, you're in serious trouble. Later on in the fight, the boss' ultimate move lets it do this to ''two party members.''
** The Devourer of Men can use Spirit Away, removing any one party member from the field until the Devourer is broken. ''It can use this move multiple times to remove multiple party members.''
** When its HP gets low enough, the Ogre Eagle will unleash a poison upon the whole party than cannot be cured and will gradually lower the party's max HP.
** Ophilia's final boss can unleash a dark flame that disables the party's area magic until being broken, which is especially problematic for healers. Given that it cannot be cured by an apothecary, the attack has the potential of turning a pretty average boss fight into a borderline ThatOneBoss.
** Granted, it's otherwise an easy boss fight, and if you're constantly applying pressure, Darius will really never get a chance to use it, but God help you if you let Darius get off his super attack; he ''steals every party member except [[FragileSpeedster Therion]]'', (if Therion is dead when this happens, enjoy a TotalPartyKill instead) which is ''really bad'' because Darius attacks three times a round, more than enough to knock Therion on his ass. Mercifully, [[AntiFrustrationFeatures while Darius constantly swaps his weaknesses, he'll always retain a weakness for daggers, a weapon Therion will always have on him, and the party members are returned if he's broken.]] What's ''not'' so merciful is that Darius has access to Unconsciousness attacks; if Therion is alone, Unconscious, and Darius has more than 2 points remaining until he breaks, you've functionally already lost.
** Any [=AoE=] attack that has a chance to inflict Unconsciousness is this. Unconsciousness functions like Sleep, except the status doesn't wear off if your character is attacked. If your entire party is Unconscious, it's all but Game Over. Examples include Mattias' Black Thunder, Darius' Hellfire[[note]]Strangely, Lucia has the same attack, but it can't inflict Unconsciousness[[/note]], and Redeye's Bestial Roar[[note]]In fact, the last one is a bigger threat than Evil Eye, Redeye's Petrification skill, if only because Redeye can use the former from the start while the latter begins to be used after Redeye is down to 50% of its max HP[[/note]]. Better come prepared with a Conscious Stone!

** The first attack used by [[FinalBoss Cackletta during the final battle with her]] in ''[[VideoGame/MarioAndLuigiSuperstarSaga Superstar Saga]]''. Because if you don't dodge, you will die instantly due to [[HPToOne both Mario Bros. being reduced to one health point at the start of the battle]] (beforehand, you get blown up by a time bomb and eaten after a HeadsIWinTailsYouLose fight). This is, of course, if your speed is lower than hers. Otherwise, you can heal immediately after the battle starts. The chances of you being faster than her are pretty low, though, since you'd've had to have leveled up to around level 34 and/or really focused on speed when using the level up bonuses and/or be using a badge that increase your speed and/or used speed up stat items.

** Avatar has Archenemy, which is Skyfall taken UpToEleven -- ''one hundred million'' dark damage to all allies. Fortunately, it only uses it once.

* ''VideoGame/EldenRing'': Want to make any fan weep? ''Waterfowl. Dance.'' The biggest attack of {{Superboss}} [[spoiler:Malenia]], this is regarded as one of the most deadly single attacks in Creator/FromSoftware history. She launches in the air before lunging at you and letting out three massive sword flurries in quick succession, attacking in a massive range around her and very easily stunlocking you into immediate death with a single nick. It can be used at a moment's notice, often jumping out of your attacks and not giving you time to recover. It attacks from all directions, meaning shields are worthless. Oh, and did we mention every single one of those dozens of slashes per flurry has a pretty sizable ''LifeDrain'' ''effect?'' Yup, even if you do manage to take the hits, she receives a large chunk of healing and undoes all your hard work getting her to that point. The only way to get through is a frame-perfect and very specific dodging sequence: run backwards away from the first flurry, roll ''into'' the second flurry (she'll move forward with it, so if you dodge away you'll get caught in the second or third flurries), then dodge backwards for the final flurry.

* ''VideoGame/EldenRing'': Want to make any fan weep? ''Waterfowl. Dance.'' The biggest attack of {{Superboss}} spoiler:Malenia, this is regarded as one of the most deadly single attacks in Creator/FromSoftware history. She launches in the air before lunging at you and letting out three massive sword flurries in quick succession, attacking in a massive range around her and very easily stunlocking you into immediate death with a single nick. It can be used at a moment's notice, often jumping out of your attacks and not giving you time to recover. It attacks from all directions, meaning shields are worthless. Oh, and did we mention every single one of those dozens of slashes per flurry has a pretty sizable ''LifeDrain'' ''effect?'' Yup, even if you do manage to take the hits, she receives a large chunk of healing and undoes all your hard work getting her to that point. The only way to get through is a frame-perfect and very specific dodging sequence: run backwards away from the first flurry, roll ''into'' the second flurry (she'll move forward with it, so if you dodge away you'll get caught in the second or third flurries), then dodge backwards for the final flurry.