That One Attack / First-Person Shooter

• ScoreDoom, a standalone Game Mod for Doom, has several egregious examples among its custom boss and miniboss monsters.
  • The Annihilator's homing missiles deal heavy damage, and are really hard to dodge, even in wide-open spaces (especially painful if said areas lack cover).
  • The winged goat demon Azazel's "stunned" state will make him shoot out ground-hugging fireballs that can rip through you, dealing incredible damage in a short amount of time. The fireballs are really fast as well.
  • The Demolisher's BFG cannon can outright obliterate you on a direct hit; however, he sometimes fires two shots, with the second one likely to finish you off; on top of that, the twin super gattling guns can shred you twice as fast if you don't hide.
  • Hellsmith's three-way explosive fireballs may as well be a One-Hit Kill on a direct hit, since each of said fireballs split into multiple explosions as well.
  • Every single one of Moloch's attacks are brutal, especially the hell grenades (very tough to dodge in tight spaces and deal massive damge) and nail barrage (these blaze through the map and rip through you for pretty large damage, and they rebound too).
  • Scourge's homing missiles can instantly kill you on a direct hit, and they're pretty fast to avoid as well. What's worse? He launches them in three sets of two. There's also that flamethrower attack of his that has a decent range but can quickly empty your health in seconds. Ouch!
  • The Dark Cardinal's homing energy ball nova attack is really annoying considering the mini fireballs home in on you and the attack goes off every time he flinches.
  • The Terminator's plasma grenade attack will total your health and armor on a direct hit, and it does severe damage if you're in the blast radius. It's a nightmare to dodge in tight spaces.
  • The Pyro Demon's teleport explosion attack is not only extremely damaging (splash damage ahoy) and a huge pain in the ass to avoid, he tends to do it pretty frequently sometimes. Mitigated somewhat in that he sometimes does it anyway even if you're not on the same level he is and he can't get down or up from there.
  • Thamuz's hard-to-avoid homing plasma ball can take you out instantly as well if it hits (that's without armor in this case); the ring of fire attack makes him invincible until he finishes the attack by sending the ground-hugging flames out (which only go straight, thankfully)
• Left 4 Dead
  • The Charger or The Jockey from Left 4 Dead 2 when on a level with ledges that kill you. A well placed charge from a charger can kill an ENTIRE TEAM.
  • Also, Smokers on a level with holes you go down but can't go back up. Three teammates drop down, and the fourth is snagged before they can follow.
    • Hunters and Jockeys are also the bane of the slow ponderous player in these situations too. Second chances are rarely given among survivor players and most players who don't "get with the programme" the first time around and fail to jump down the right hole at the same time as the rest of the team are often summarily booted from the game if they get pinned/snared and become unsaveable.
    • Likewise for infected players, it is extremely difficult to pin/snare a survivor player and kill them before their buddies shoot you and rescue them (you are vulnerable to other players when pinning one and cannot move until your pinned target is dead). Therefore pinning/snaring a slow, clueless survivor player who didn't jump down the one-way hole at the same time as the rest of the survivor team is seen as a Moment of Awesome for the infected side and a benchmark by which to measure a player's skill as an infected.
  • Anything from the Tank. On Expert, both of his attacks will incapacitate you in one hit, and he's scarily accurate with the cement throw^note If you are facing against an AI Tank, change directions at soon as he throws and you can usually dodge the rock throw. On any other difficulty, one of his punches sends you flying, which can range from being a minor nuisance to sending you flying off a bridge/rooftop to your instant death, and the developers love putting instant death falls on finale levels, the only place where you're definitely running into a Tank. And you don't respawn during the finale event. Punching cars/debris counts too since it's another instant incap, regardless of difficulty.
  • Any attack in the game that damages also causes flinching, the Common Infected will reduce your speed to nothing if three or more are hitting you at the same time.
  • For anyone playing as the Special Infected, the Survivors' melee attack will stagger you long enough for them to move away and kill you, or they could kill you using just the melee attack if they're feeling sadistic, which most people are in Online Versus.
  • It gets even worse for the Tank: if your Tank dosn't have access to cars or cover to get to the survivors, the survivors will simply shoot the Tank player from a distance. Each shot causes flinching which will slow the Tank; with all four survivors wielding machineguns in a wide open area without any cars to throw, the Tank usually dies in seconds when survivor teams do this.
  • One attack from survivor players annoy the hell out of Tank players: Fire. If they hear a Tank appear, survivor players will use their molotovs as soon as the Tank player is in their sights or shoot nearby gas cans as a substitute. Once caught on fire, the Tank will keep taking damage until it dies, frustrating the infected team to no end. If there's any water nearby, then you're not as screwed.
• Team Fortress 2:
  • The Degreaser + Axtinguisher combo. The Degreaser is a flamethrower that allows the user to switch weapons much faster, while the Axtinguisher always deals a Critical Hit if whatever it hits is on fire but deals reduced damage otherwise. Together, this means if you get in the range of a Pyro with this combination, you're dead. You will be lit on fire and struck with a 195-damage attack that will One-Hit Kill anything but a Heavy within less than one-and-a-half seconds. Some Pyros use the "Puff & Sting" combination, where they use the compression blast feature to push you into a wall, disorienting you and preventing you from fighting back, and then One Hit Killing you. Fortunately, the Love & War Update changed the Axtinguisher so that attacks from the front only result in a mini-crit, not a normal crit. ^* Mini-crits deal 35% more damage than normal. Critical hits deal 200% more damage. That's a big difference. This means Pyros can't just shove you into a wall and kill you as quickly as before. If one sneaks up on you from behind and you don't notice, though, you're fair game: attacks from behind still result in crits.
  • During the Halloween 2013 event, there were several "magic spells" that could be used. The most annoying was the Ball O' Bats. It's a thrown projectile that explodes, throwing whatever it hits into the air and causing bleed (damage over time). The blast radius for this projectile is deceptively large, and whoever gets hit goes flying straight up. If players were being chased, they could just use this, knock their assailant into the troposphere, and escape. It was also a very common spell to obtain. As such, it was a relief that the next year's Halloween event map didn't have them.
  • The Spy's Red-Tape Recorder. It's a sapper that, instead of dealing damage, reverses the construction of the building it's attached to. This happens very quickly, meaning that it takes about 6 seconds of inattention for a building to be set back to level 1. It's horrible at actually destroying buildings (the initial building time is much longer than the upgrade time), but it's very good at wasting Engineers' efforts and time.
  • The Engineer's Pomson 6000 is a ray gun that needs no ammo, though it still needs reloading. If it hits, it drains up to 20% Cloak or up to 10% Medigun Charge. Considering Uber advantage is deciding factor in matches, getting hit even once will turn an Uber push into a '90% Uber drop'.
• Borderlands:
  • The first game has the Roid Rage Psycho's Grenades. The boss seems easy and it's child's play to snipe his overly large head. And then he throws a grenade that will completely destroy your health and shields if it hits, leaving you open for him to kill you. To make it worse, he has a spread mod, so every single grenade will spit up into 6.
  • The Destroyer's shockwave attack. It's not very damaging, oh no. There are two issues: First, it pushes you out of cover, so it can get you with it's other attacks (Plus it's a pain to keep running back to cover) and two, prepare to throw your controller against the screen if you happen to be even remotely close to the edge when he uses it.
  • Wilhelm in the sequel has one. When the fight begins, there's a train car in the area you find him...and he makes his entrance by coming out from underneath that train car and throwing it. If you're standing near it, you die. You don't go into Fight For Your Life, you die. Fortunately, this only happens once.
  • A Christmas peril so terrible you'll feel nostalgic for your racist uncle and waiting four hours in line to buy presents, Tinder Snowflake's rush attack in the "How Marcus Saved Mercenary Day" DLC is devastating. All of his attacks are nasty due to high damage and accuracy, but the rush attack is much worse: he moves very quickly, hits very hard, and can do it up to four times in a row, and to make matters worse he's immune to all damage while doing it. There are areas where he can't hit you with it, such as the entrance, near the lift...but that's a very confined space, and he takes up most of the entrance, meaning you're easy prey for his devastating but short-ranged frost breath attack. At least the presents are good afterwards (a train with a huge quantity of items will turn up whenever Snowflake goes down). This attack becomes even worse when playing as the Commando, as deploying your sabre turret will cause Snowflake to immediately use it on your turret and instantly destroy it. Without the Mag-Lock upgrade to allow you to safely stick the turret on a wall out of reach, the Commando is stripped of his main source of damage output for the duration of this fight.
• Overwatch has Roadhog in general.
  • Every player will learn to HATE his chain. Have a 200HP hero? Say goodnight! Playing as a 150 HP cheerful british lass? He can one shot you even without a hook. Playing as a sniper with wide hips? That 25 HP nerf that happened recently isn't going to help your situation. Oh having 250 HP or being a Tank doesn't quite mean you will win after the initial damage either.
  • The Chain itself without a followup shot from the big pig is rather dangerous. He can turn around up to 90 degrees while pulling you in to change your final ending zone. If there is a hole nearby the hog can make your player fall into it. A hog can in some instances use the trick also to pull an enemy in a room and proceed to body block said opponent to prevent the opponent's escape and let his team kill the pulled in enemy while the hog reloads.
  • Are you almost done killing the hog? Watch him use his healing ability to recover 300 of his 600 total HP. Oh and he takes half health while recovering. Good job with that Pulse Bomb you stuck on hog Tracer! Watch him just use his recovery before it explodes to half the damage and recover all of it back plus some more. Oh every time he does this when he has less than 300 HP he gains 19% of his ultimate. Oh, and if Anna bionades him ignoring the HP recovery from the impact, he recovers 450HP from doing this.
  • As Winston, you will learn to LOATHE Roadhog, since Winston literally can't beat him one-on-one. Oh did you manage to rocket jump away? Watch hog pull you back in. Have you used Primal Rage? His ultimate Whole Hog perfectly counters you by doing massive damage that eats through your 1000 HP easily if you get trapped in a corner or he can just shoot at you and push you away throughout your whole ultimate duration.
• ULTRAKILL:
  • Multiple bosses have the ability to summon a black hole-esque purple sphere with massive AOE and homing abilities, which drains your health to a single point within seconds and hits you with Hard Damage to make sure you can't just immediately heal it back up. This is already troublesome against the Corpse of King Minos, because it ensures any of his following attacks (telegraphed as they are) could instakill you. When you face the Flesh Prison, which can summon this without warning and pelts you with Bullet Hell barrages all the while, it becomes a nightmare.
  • Minos Prime has two especially infamous attacks. The first is his serpent projectile, which comes out with less warning than his other attacks, travels insanely fast and homes in so tightly you need to dodge perfectly or parry it if you want to avoid it; he can outright spam this one in his second phase. The second is his iconic "JUDGEMENT" dropkick, which while having very visible windup hits damn near instantly, needs to be parried and dodged to fully avoid the damage thanks to the explosion it sets off, and makes sure Minos himself is right in your face afterwards to combo into one of his other attacks.
  • When Sisyphus Prime tells you "THIS WILL HURT.", he means it: The attack that follows is a massive explosion that covers so much of the arena dashing out is rarely an option. You will either need to abuse the dash's invincibility frames, or just commit, get right in his face (AKA the epicenter) and try to parry him before he can do it. Screw this up and say goodbye to half your health bar, in a fight where the boss can otherwise take you out in three hits.

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