That One Attack / Platform Game

• Donkey Kong:
  • Tiki Tong, the final boss of Donkey Kong Country Returns, has one attack where he will place his hands vertically at either side of the screen (or just one if one hand has been destroyed) and slam them together. It is nearly impossible to dodge, because the timing for when he will slam his hands together after placing them is not the same every time he does it. The only way to tell when he's about to slam them together is that they show a little flash, which comes a fraction of a second before the slam. Unless you have very good reflexes/reaction time, you will get squashed in between, losing one of your precious two hit points (or four the first time through)...unless you're playing on Mirror Mode, in which case the first half of the boss battle might as well be a Luck-Based Mission. If you are lucky, he won't use that attack and instantly kill you. Unless you trick it out by bouncing off his hand before he slams it. But even then, he can fake out the slam and then crush you.
  • Lord Fredrik from Donkey Kong Country: Tropical Freeze has an attack in his last phase where he causes all the platforms to rise up and then fall into the lava. Dodging it requires you to jump to where the first platform to fall was before it actually rises up from the lava again which is not only counterintuitive but very difficult without Diddy or Dixie.
• The East New World has the fiery breath of the Fire Dragon. It is extremely hard to avoid, requiring you to go all the way through an arena full of traps to do so, and if it gets you, it's an instakill. It's also his very first attack.
• Lord Brevon's knife attack in Freedom Planet. It comes out very quickly, takes off half your health, and can be deceptively difficult to dodge. Adding insult to injury, it's the very first attack Brevon pulls out during the final phase of the Final Boss fight. You will get hit by it the first time you see it.
• The last attack of the boss fight in the LittleBigPlanet 2 The Muppets Pack is this. Basically, the boss begins slamming his hands on the ground, causing flaming debris to fall from the ceiling. The debris is very large and it falls very quickly, while the attack in question lasts for 20 seconds. It's very easy to lose your Ace run to that attack alone.
• Kirby
  • Star Dream Soul OS's Desperation Attack in Kirby: Planet Robobot that it uses upon death. It fires three waves of energy rings, the last of which fires two at once, each of which covers a large part of the screen and does roughly 90% of your health in damage! Oh, and they also completely ignore guarding and invincibility from things like Stone, Archer and Leaf, meaning that unless you've got ESP's teleport attack (which removes Kirby from the screen entirely), you have to dodge the attack, which is precise and hard to do. The worst part is that it comes after a 30+ minute gauntlet of souped-up versions of all the bosses in the game and you're at half-health at best; this attack coming out of nowhere and insta-killing you can lead to rage and a broken 3DS, and is still tricky even if you know it's coming.
  • The Mage-Sisters from Kirby Star Allies each have super-attacks which fill lots of real estate on the screen — Francisca has a bouncing soda-gun spray, Flamberge has an incendiary cannon, and Partizanne has a lightning beam attack. While these attacks aren't That One Attack by themselves, as they're easy to dodge and can be interrupted to daze the girl in question, the rematch with all three in "Heroes in Another Dimension" pits you against exactly that at the halfway point. Even worse, the first time this combination is used, they're staggered so getting hit by one launches you right into the next one in succession, and you have a short window to dodge the next one in turn. Do not count on AI allies evading this attack in any capacity. And for the capper, you will have to endure this onslaught during the Soul Melter EX version of The Ultimate Choice. If you get hit by Flamberge's Mega Broiler during this gauntlet from Dark Star, kiss your run goodbye.
• Mega Man X
  • Violen's Epic Flail attack in Mega Man X2. It does massive damage and has no discernible pattern to dodge. Even with the body armor upgrade to reduce the damage by half it still takes a good chunk of health every time it hits you.
  • In Mega Man X5, the fight with Zero has him throwing nearly-full-screen Sword Beams that you have to dodge in sequence. Capcom acknowledged this by making this attack Zero's Level 3 Hyper Combo in Marvel vs. Capcom 3.
  • God help you if you're fighting Maverick Zero. His variation of that attack inflicts instant death or close to it, and if you should leave him at low health for too long, he will back into a corner and fire that attack continuously until one of you is dead. Fun.
  • Bamboo Pandamonium's desperation attack in Mega Man X8. Like every boss with such a move, he telegraphs it, but that won't help you; the punch he throws is sudden, fast, its hitbox takes up over half the screen, and deals an obscene amount of damage. On Normal and Hard, if you've not bought enough life gauge upgrades, you dodge it or you lose a character. The attack is specifically designed to one-shot Ride Armour, which makes the fight much easier if you managed to maneuver it to his arena, as it allows you to continuously pummel him while taking zero damage, until the Armour is inevitably destroyed. Better be confident in your reflexes if you're not in Ride Armour when that attack begins... but there is no Ride Armour when you fight him again in the Boss Rush. Hope you've got full Life Tanks!
  • Lumine:
    • His first form uses the desperation attacks of the 8 Reploid bosses, including the one mentioned above. However, there are two attacks that he modified; Avalanche Yeti's attack, which causes gigantic snowflakes that freeze you on contact to rain down, lasts a lot longer, and Lumine can still blast you with other attacks while it's in effect. And then Burn Rooster's attack, which engulfs the walls in flames, never wears off. After it hits the field, you can no longer wall-jump.
    • His second form: When his health dips low, he uses an attack that makes darkness start enveloping the screen while he Teleport Spams. If you don't kill him within 30 seconds, you die, and you have the pleasure of taking on the first form all over again!
• Wily's second form in Mega Man 7 is often considered one of the most unfairly difficult fights in the series, and the majority of that reason is because of one attack that he spams constantly, summoning four differently-colored balls of energy that lunge forward at Mega Man three times. The attack is nigh-impossible to dodge (you have the best chance if Mega Man and Wily are on the extreme opposite ends of the screen, but it still requires perfect timing), does anywhere from a decent amount of damage to taking out huge chunks of the player's life bar (especially if they get frozen by the blue sphere and can't break free fast enough to escape from Wily's follow-up attack) and is used every time he teleports. You know it's terrible when "Just get hit by one of the yellow spheres because they do less damage" is a perfectly reasonable strategy.
• Dynamo Man in Mega Man & Bass is mostly a pretty standard, if challenging boss... until he breaks out that recharge chamber. Every so often, he leaps to the top of the screen to a machine that comes out of the ceiling, and while he's in that machine, he'll regain health. Lots of health. As in, "he can go from nearly dead to full in a single jump" lots of health. As in, "even if you can get off a Copy Vision and have the copy shoot him while he's up there, the healing is so fast that it outpaces you hitting him with his weakness" lots of health. The only way to keep it from happening is to break the machine, but that requires you to break both sides of it, and it's on the ceiling. Bass can break it while on the ground, but Mega Man has no such luck.
• Mega Man Network Transmission:
  • FireMan has two; his regular attack which is only dodgeable with good slide timing, and takes off a good chunk of your health. And when his HP gets low, he periodically bursts into a pillar of flame. If you're near him, it's a One-Hit Kill without the Heat Armor (when you first fight him), and an absurd amount of damage with it. And this is the game's first boss!
  • Zero has an attack where he lets loose an energy wave that takes up the whole screen and does 300 damage, a possible reference to the original Zero's Sword Beam attack mentioned above. God help you if you didn't pack an Invis.
• Mega Man ZX Advent:
  • Chronoforce has an attack where he swims into the background, shoots homing icicles at you, then reverses time to make them unexplode and fly back to him. If you didn't memorize where the icicles went you will get hit at least once as they rewind.
  • Another attack of his shoots icicles in roughly a 90-degree arc, with holes in between each icicle. However, on Expert Mode, he shoots off an extra set that goes in between the shots of the first one, making it nigh-unavoidable. Also, because you're playing Expert Mode, Chronoforce will have a permanent Time Bomb active, so all his attacks move twice as fast as they normally would.
  • Queenbee's giant laser beam attack also deserves mention. Unpredictable, nigh-impossible to dodge, and she will use it at least once.
• Jak II: Renegade:
  • First confrontation with Baron Praxis is rather nasty, but manageable until the third part. There, he starts shooting multiple fiery tornadoes at you at once that move in erratic patterns and are very hard to dodge due to how difficult is to predict their trajectory. Moreover each stage of this boss takes many shots to defeat, which leaves you open at this attack for the final third - it is not uncommon to get hit by another immediately after your Mercy Invincibility expires.
• Ratchet & Clank (2002):
  • Drek is difficult boss even for a Final Boss, mainly because two of his attacks make him harder than needed:
    • During last two sections of his health bar, he starts shooting you with a BFG which he used to nuke two plateaux at the beginning of the fight with him - he moves out of the arena, then shoots you with multiple shots consecutively. The shots are big, fast and hard to dodge, so you must be moving constantly while he shoots them otherwise you'll meet the same fate as those two islands. The absence of strafing makes it all that harder.
    • During the last section of the health bar, a green missiles start to swarm the arena constantly, while Drek himself is still attacking you and you're supposed to take care of that timer as well. Not easy to not take a hit, which you probably can't afford at this stage of fight.
• The game A Smile Is Beautiful, a Spiritual Successor to The East New World, has the arrow barrage of Meng Donxin. Meng will jump to one edge of the screen and fire arrows from above with a terrifying speed and accuracy. It's very hard to not get hit. And God help you if there are enemies nearby: the animation of him preparing the attack stops you but not the minions, meaning you can get a free hit from them.
• Super Mario World ROM Hack VIP & Wall & Alaska Mix 5 has the final boss Julius' second phase, where one attack consists of him creating two doubles which each fire two fireballs at you. What makes this That One Attack isn't that it's hard to dodge, it's that this is the only part of this phase where you can do damage to Julius, by getting his doubles' fireballs to hit Julius instead of the player, but as raocow demonstrates in his LP of the game, the real Julius can sometimes appear above his doubles, rendering him pretty much impossible to hit, and he can do this several times in a row, wasting massive amounts of time.
• Sonic the Hedgehog:
  • The suicide attack by the Egg Viper in Sonic Adventure, if only because of the horrid camera angle.
  • Some of the boss battles in Sonic Rush (and the Sky Canyon boss in Sonic Advance 2) have instant death attacks, or attacks which are nearly impossible to avoid consistently. The ones in Sonic Rush are very well-telegraphed, though: Probably the only hard one to see coming is the one where Eggman (or Nega) rams his giant robot's shoulder spikes into the stage at the end of said battle, mostly because you've never seen it before. The button-mashing on the Sonic vs. Blaze battle would be hard to see coming as well if it weren't for the mini-cutscene and the fact that one boss earlier used an easier version of the button-mashing gimmick.
  • Silver's psychokinesis in Sonic the Hedgehog (2006). He grabs Sonic/Shadow and slams them into a wall or tosses them into the sky. When the attack starts, it cannot be broken out of. If he slams you into a wall that is close by, or tosses you straight up, he WILL catch you with it again immediately before you can start moving again, ignoring mercy invincibility, and proceed to kill you, or, if you manage to repeatedly land on dropped rings, catch you in an infinite loop. And it can lead to a Game-Breaking Bug if you're in the wrong spot - if there are no buildings where he throws you, you just fly off into space and never land.
• In Ori and the Will of the Wisps, each of the major bosses has at least one highly-hated attack:
  • Mora has a highly damaging straight laser attack with very little advance warning during her second phase, and due to the glitchy nature of the Grapple plant, can result in taking unavoidable hits, making the "Untouchable" achievement a Luck-Based Mission.
  • Corrupted Kwolok, after he Turns Red and floods the arena, deploys an attack in which he spits four purple gobs that leave poisonous trails in the water for up to ten seconds, making dodging other attacks a hassle. And since you can't use the Regenerate spell underwater, the only way to regain HP is by random drops from dash-attacking the Stink Spirit's highly-unpredictable Combat Tentacles.
  • The Big Bad Final Boss Shriek has her Dash Attack, which can knock off up to half of Ori's HP on Hard mode. At first, it's telegraphed well in advance, but after she Turns Red and takes the battle to the skies, she spams it in much more rapid succession.

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