That One Attack/Video Games/Role-Playing Game

Examples of in s include:

Other Examples

 * Many examples in Lord of the Rings: The Third Age.
 * 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 Mumakil. Hits everybody, and stuns them. Stand Fast makes it mostly worthless (it's still kinda painful), but if it gets it off before Berethor gets a turn... Well, you're 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.
 * Cruel Ruin and Djinn Storm from Golden Sun: The Lost Age's Doom Dragon.
 * Literally every attack done by Dullahan counts as That One Attack. Dark Dawn might have been disappointingly easy, but Dullahan somehow got even harder.
 * Djinn Blast is a lesser cousin, but no less aggravating. Used by the Chaos Chimera in Dark Dawn and by Karthas in The Lost Age.
 * Ghoul Ball used Consume Djinn! Sveta's Fleet was eaten! Player's anger increased by 100!
 * The Ancient Devil's Demon Sign takes over one of your characters. And they can use your djinn for summons, though they won't always do this.
 * The fangame Labyrinth of Touhou borrowed Djinn Storm, and it is every bit as annoying (Empties all party members' SP, including the SP of those in reserve).
 * The Chaos Chimera has Retribution, an 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.
 * Cunning Blow in Magi Nation.
 * In Digimon World 3, 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 Pokémon, sleep makes it pretty much impossible to escape and definitely impossible to attack, making your Digimon a sitting duck for Vademon.
 * There's also 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.
 * Digimon World Dawn and Dusk has Chrono Destroyer, only useable by the final boss. High Dark damage, plus it can easily put your whole party to sleep.
 * 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.
 * You'll be hard-pressed to find a veteran player of the Dragon Quest franchise who doesn't hate Disruptive Wave with a passion. What it does is that once the enemy uses it, ALL your buffs are gone and there is NO way to block it, leaving you with a huge disadvantage if you spent the last 3 rounds casting buff spells, which you absolutely need in the endgame, and need a heal badly. Did we mention that pretty much 95% of the bosses in the game have access to this ablility and some of them like to spam it like crazy??
 * 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. Have fun getting around that.
 * 's Magic Burst in IX. Nothing more needs to be said.
 * Palaxius has a lot of cringe-worthy attacks, but Crimson Split stands out. It can easily deal up to 300 to every character (which will most likely kill any character except for Felt and Gray) and once he casts it, it sticks around on the time bar to come up at least four more times while he keeps pounding you. Did I mention he's lightning fast and his other main attacks hit for even more damage? Luckily, Crimson Moon and Shadow Azoth are can only target one character.
 * Wild ARMs has a take on Bad Breath called "Arc en Ciel" which does some damage along with said status blast. Expect it to be used by the aliens.
 * Kingdom Hearts:
 * In every Kingdom Hearts game, Riku has an attack entitled Dark Aura, wherein he'll become invincible and fly in quick dashes at your character. 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 you can use it yourself as Riku. Also, Ansem's ultimate attack in Riku's last battle with him will almost certainly be fatal unless you dodge it.
 * Bonus Boss 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 HP to One 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 Action Command, otherwise you pretty much die. At least you don't lose that much progress if you mess up...
 * Xaldin's Wind Dragon in the Kingdom Hearts II. 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.
 * Birth By Sleep has the nameless optional boss 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 pretty much 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 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 Armor of the Master and No Heart from the final mix of Birth by Sleep each have their own. Aot M has a 20 hit combo almost guaranteed to reduce your HP to one normally, but if he's been allowed to enter his Super Mode by sapping you with his chain, it's a guaranteed kill. No Heart has his own variant of Heartless Angel late in his battle. It's uninterruptible but can be avoided, but if you either fall into one of his slow traps or are right next to him when he rises into the air you will be hit. This is also a guaranteed kill if he uses it twice, unless you have an item which you'll likely have used up by then.
 * Ever wonder why everyone hates 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 bypass Second Chance/Once More if your HP was already depleted to one by then.   He can pull this combo off at will, and this makes it very hard to hit him. He also has  it's unblockable, it is difficult to knock him out of it, and he can use it up to THREE TIMES IN A ROW.
 * 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 Kingdom Hearts 358 Days Over 2, 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 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 Birth By Sleep. 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.
 * Demyx from Kingdom Hearts II has a very annoying attack where he says, "Dance, water, dance!" and you have to kill ten water clones of him in ten seconds. Fail to do so? Instant death. It will probably be the biggest cause of frustration for you when you fight him.
 * Romancing SaGa: Three words—Open the Gate. Death likes spamming this a lot; it pretty much kills your characters outright or heavily damages them.
 * Or even worse: Jewel Blaster, which deals magical damage, not physical. 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.
 * 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 Limit Break but you probably wouldn't know that on your first try
 * Manah in the canon ending was a pain it the butt. She had this annoying attack in the middle of the fight where she would summon rings that came from her abdomen, not too bad. However, after taking so much health from her she decides to summon the rings from all angles... Have fun dodging those.
 * In Paper Mario: The Thousand-Year Door, 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. 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.
 * On the topic of the Audience Cannon, just like it 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 Limit Break) from.
 * One completely unguarded sequence of the Audience Cannon would probably not be enough to kill you in one go, although the reality wouldn't be much better considering that at that point you'd probably have roughly 50 or so HP, so it probably would kill you in two.
 * The first Paper Mario game has Tubba Blubba's heart attack (Though it can be dodged by using Outta Sight), General Guys 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 Brother's 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).
 * 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.
 * In the Mario & Luigi series:
 * Two of Bowser X's attacks in 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 pretty much 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. Did we mention how fast he goes?
 * In Bowser's Inside Story, the Junker seems like a fairly standard Flunky Boss...until he sucks Luigi up and sticks him inside one of his flunkies. The attack is unavoidable, 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 it's 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 first attack used by Cackletta's soul in Superstar Saga. Because if you don't dodge, you will die instantly due to having only one health at the start of the battle (beforehand, you get blown up by a time bomb and eaten after a Hopeless Boss 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 that 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.
 * There's also the giant laser/fire breath beam attack used by five bosses in Mario & Luigi: 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 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 too 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, did I mention it does a lot of damage?
 * In Super Mario RPG, 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.
 * Any instant-death attack counts as this, unless you've equipped accessories that block them (or, for certain ones, have really good timing).
 * When Smithy is in his wizard form, Sword Rain, Spear Rain, Arrow Rain and Dark Star count heavily. Also, his chest form uses different status effects on you, and Tank Form has an instant death attack.
 * Yaridovich and his Water Blast has downed many a low-level run player.
 * Carni-Kiss is a really powerful attack. It's not a One-Hit Kill, 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 Monsters and Shogun pack it, which doesn't help matters. Very ironically, by the time you fight the Chomps that know it, it's not as dangerous.
 * Where are the aoe crowd control spells here? Petal blast? Light beam? Both of which will disable your entire party until the boss feels like pwning you? Seriously, any boss with either one of those attacks turns it into a luck based mission.
 * 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 pretty much impossible to block unless you instantly press A as soon as it's his turn to move. Even when you 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. It's ridiculous.
 * Don't forget his Dark Star special, as well, which is armor-piercing and can pose a serious threat even to a Lazy-Shell-equipped Toadstool. At least it's only single-target.
 * Chrono Trigger has several, though the New Game+ eases the pain of some of this:
 * Masa and Mune's combined form has an attack, signaled by the message "Storing Tornado Energy." and two turns later "Pain...", that does over 100 HP in damage and targets the entire party. At the time you face them, it will most likely knock your characters into the low double-digits and force you to waste a turn healing them. Even worse, the single obscure hint given by a random NPC that tells you how to stop the attack was mistranslated into uselessness in the original SNES release of the game..
 * Magus risks casting a spell! (Signals that he's about to cast Dark Matter, his most powerful spell)
 * Barrier Change: Only Shadow damages! (Magus' Barrier Change spells not only make him immune to all magic except the corresponding element, they also hit the entire party hard. And he does them a lot)
 * Destruction rains from the heavens! (Lavos shoots his Spines of Death at you)
 * Lavos Core's "Grand Stone" attack, guaranteed to reduce you to single HP digits, if not kill you outright (but you can use this against him if you have Frog and/or Ayla in your party) Also Dreamreaver, which is basically the same attack, just a magic variant. Chances are it'll do more damage to your party than Grandstone. On the plus side, his attacks can be predicted. If you pay attention to the shifting background, you'll see his attack corresponds to the time period showing. This way you can at least prepare for the the pain that's to follow. Good luck with the actual damage though.
 * Any attack involving both of Giga Gaia's hands. The problem isn't the attacks per se, it's that, on a first run, Giga Gaia is almost guaranteed to go first and act twice in a row, and the Double Handblaster/Dark Plasma combo WILL Total Party Kill you if you aren't prepared (which boils down to having either insanely high resistance or outright immunity to at least one of the two elements he uses).
 * Queen Zeal's Hallation, which also drops the party's health to 1 HP. If that isn't enough, attacking her hands in her One-Winged Angel form causes them to counter with Hallation and MP Buster. Good luck recovering from that.
 * Son of Sun's flare and purple laser both take a huge chunk of HP (potentially over 300) out of pretty much any character who isn't appropriately equipped. While only Flare targets the entire party, its AI loop places the attacks right after each other.
 * The DS version adds a couple new ones, such as Scintillation. Thankfully only used by one boss, this attack deals an absurd amount of damage to the whole party - absurd meaning roughly 400 at maximum magic defense and with a Barrier that halves magic damage, in a game where the HP cap is 999. And if you have a character with less than maximum magic defense or remaining HP, better hope the boss doesn't recast it while you revive said character on top of healing your party.
 * Then, we got Chrono Cross.
 * Miguel and all of his white magic, but especially HolyDragSwd, which is so tremendously powerful it can almost one-shot anyone who isn't innately white. And he likes comboing it with WeakMinded, a magic-defense debuff. And if he manages to turn the field white...
 * Pretty much every element used by the Tragediennes. This is the entire point of them; if you can survive their initial volley of elements (and had the foresight to bring the right traps), you can acquire stuff like Volcano and BlackHole way ahead of schedule, essentially breaking the game wide open.
 * MegaStarky, otherwise a fairly easy boss, will smack the party with an UltraNova when his health drops far enough.
 * ExhaustGas, used by the Highwayman in the Dead Sea, blinds the entire party and is very accurate. You'd better have some BlackOut or Purify elements allocated, because you're not winning this fight with everyone blinded.
 * attacks are pretty much 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.
 * The gets access to pretty much all the elements in the game, including nasty ones like BlackHole and UltraNova; when you add that to its already staggering magic attack, you've got a recipe for a party wipe. You can stop them with traps, if you know they're coming, but if you don't know about them, it's a long road back to Marbule.
 * Insanity Prelude in Star Ocean 3, 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 SO3 message board is inevitably hit with 'how do I dodge Insanity Prelude' more than a few times.
 * While several of the Nintendo Hard extra bosses have similar moves, the final three of Lenneth, the Etherial 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, oh let's say, three seconds, before she's back on the offense.
 * The trick with Ether Strike is to make sure she's nowhere near the center of the battlefield when she uses it. The move is slow enough that you can make it to the other side of the field, so it's in your best interest to simply keep her pinned on one side of the battlefield by luring her there. The first minute or two of the battle can be pretty rough though, as you must survive her attacks long enough for her to GET to the battlefield's side. Or alternatively, abuse Fayt's Side Kick which has invincibility frames and lets him completely dodge it...
 * Fadroh in Baten Kaitos is a Curb Stomp Battle. Who is curb-stomping who? That depends entirely on whether or not Fadroh buffs himself with Orb of Magical Offense.
 * Forfeit Your Life, a One Hit KO. 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 Turns Red 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 One-Hit Kill, but might as well be.
 * The Holoholobird's Wingflail, which knocks the whole party down and breaks any combos you've set up.
 * . 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, that 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.
 * 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 . 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.
 * When you see the eponymous boss of Diablo II step back, run like hell because he's about to unleash 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.
 * Some enemies in Dragon Age Origins will use the same Game Breaker abilities that you use all the time. It's no fun at all being on the receiving end of a Crushing Prison (continuous damage and paralysis), Overwhelm (essentially a physical version of Crushing Prison), Scattershot (ranged mass stun that's almost impossible to resist), or "Curse of Mortality" (negates healing and does continuous damage). That last one is almost guaranteed to result in character death (which is extremely annoying if you're going for the "No Deaths" achievement) unless it's dispelled. Some bosses  also have grab attacks that can instantly kill any of your party members except for the unique ones like Dog and Shale, which makes those two good choices for fighting against  . You will also quickly hate the Revenant's "Pull" attack when it brings your precious mage or archer within range of that BFS.
 * There is only one thing worse than Pull: Mass Pull. Nothing beats getting all your party members yanked off their feet and into melee range, often interrupting vital spells or talents.
 * BLOOD WOUND. It's like Crushing Prison, only for your whole party at once! Very likely to end your game. Always shoot the blood mage first.
 * The Limit Break of the final boss in Tales of Graces kills at least two of your party members, unless you're fighting on easy mode. If you're unlucky, it will obliterate your entire party.
 * Also from Tales of Graces, there's  with her Killing Field spell she always uses immediately after entering Arles Rise, which hits the entire battlefield, and is likely to put everyone into critical HP or KO them on higher difficulties if they don't defend against it (Which the AI is quite prone to).
 * Tales of Symphonia has Retribution, which the first form of the Final Boss uses -- and then adds to its AI Roulette—when you get him down to about half of his HP. It gives two random status ailments to each of your party members. The catch? It's unavoidable, unstoppable, and chances are that two of said party members are going to be poisoned (and at least one of them paralyzed).
 * Fly, o Holy Sword! Brilliant Cataclysm! Cue Party Wipe.
 * Toll the beginning of time... Big Bang! This one isn't as bad, since he may use it once or twice and that's easily countered by a Treat. But if you fight the optional boss? I guarantee you'll be sick of hearing that. Oh yeah, and did I mention he has something else in his arsenal, too? (And yes, the final boss heals.)
 * Big Bang is even worse in the Play Station 3 version, as it actually has the capability of killing you on higher difficulties. Did I mention that it can do upwards of 80,000 damage on Unknown mode (meaning even Flynn's Energy Coat can't save you)?
 * In Tales of the Abyss, most enemy Mystic Artes are avoidable, assuming they don't pull one out of nowhere without warning. Arietta's, though? Big Bang hits everyone completely regardless of where they are on the field.
 * The optional bosses get pretty bad too. Philia has Big Bang and Sacred Penance which both are usually guaranteed to hit you. Reid also can use Aurora Wall. Hits everyone nearby, which isn't bad... but did I mention that it REVIVES the fallen comrades? And Nebilim... Big Bang, Mystic Cage, Fortune's Arc, Indignation, Rending Saber, Radiant Howl, and the worst one yet, the only one she didn't steal from your party members... Fragmented End. Basically? If she does this... you're gonna be reeling if you survived.
 * In Tales of the World: Radiant Mythology, Widdershin can use Eternal Finality (Nereid/Shizel's ultimate attack which required a specific counter or it'd be an instant game over as it dealt 20k damage and healed Nereid completely) once he drops to half health. The good news: It doesn't heal Widdershin completely and does a lot less damage. The bad news: it still hits for 5000+ damage AND there's no Aurora Wall to counter it in this game, so you know it's gonna hurt.
 * If you're not prepared for it, the spell Harm from Dungeons & Dragons can qualify. A successful shot will reduce you to 1d4 HP regardless of how many you have. (Granted, it can be resisted, saved against, interrupted, countered, etc.) And there's the arguably-more-annoying reverse spell, Heal, that can restore a boss to full health from whatever it happens to be at. This is precisely why Harm and Heal were capped to 150 points of damage or healing in 3.5 Edition.
 * The developers of 3.5 consider any attack which results in level loss to be A Fate Worse Than Death, and grounds for immediately rolling a new character.
 * In Pokémon Diamond and Pearl, Lucian's Bronzong has an incredibly frustrating one: CALM MIND. Bronzong is one of the most difficult Pokémon in the game to KO with physical attacks, so naturally you're encouraged to go with special attacks. What does Calm Mind do? It increases Bronzong's Special Defense AND Special Attack, so not only is it nigh impossible to knock out after a single use, its attacks are much stronger. Worse, Bronzong can use this up to six times. After about 4, ALL of Bronzong's other attacks are That One Attack, and it only gets worse from there. Thanks to this, Bronzong, by itself, is more difficult to defeat than the Champion's entire team. Which is why Bronzong was nerfed a full 11 levels in Platinum. And There Was Much Rejoicing.
 * Other examples:
 * In Gen. I, if your Pokémon is slow enough, "Ekans used Wrap! Ekans's attack continues!" Again and again and again. (This was fixed in the later games. Wrap no longer holds your Pokemon to keep it from attacking.)
 * The foe's Clefable used Metronome! The foe's Clefable used Volt Tackle! It's super effective! Gyarados fainted!
 * The wild Mew used Transform! (Only applicable in Red, Blue, and Yellow.)
 * The foe's Articuno used Sheer Cold! Sheer Cold (and other OHKO attacks) only have 30% accuracy.Though, that apparently only applies to you.
 * On the topic of attacks hitting more often than they should, Hydro Pump, Blizzard, and Thunder are notorious for not always hitting. However, the computer will always hit if you're at all weak to the attack.
 * The foe's Alakazam/Mewtwo used Psychic! (In Gen. I, though it can easilly OHKO anything without explicit resistence.)
 * The foe's Aerodactyl used Stealth Rock!
 * Any Psychic-type move, but especially Psybeam, Dream Eater, and Psychic. Unless you're using a Dark-type, watch out. Wait, you're playing Red, Blue, or Yellow? Sucks to be you! Also, Hyper Beam for any Dragon-type.
 * Earthquake. 'Nuff said.
 * Wild Voltorb used Selfdestruct! Or worse: Shiny Graveler used Explosion!
 * Whitney's Miltank used Rollout! And if you're playing Heart Gold? Miltank used Stomp. *insert Pokémon you're using here* flinched.
 * On that note, any move that can cause Pokémon to flinch. For every tale of glorious victory by causing the enemy to flinch, there are several others mourning the loss due to having a 'Mon flinch at the wrong time.
 * Destiny Bond, a move that, when used, takes the opposing Pokémon down if the user is knocked out.
 * Any attack that causes confusion, particularly Confuse Ray. Since The Computer Is a Cheating Bastard, the next 5 turns will have your Pokémon "hurting itself in its confusion". Naturally, that's only true for YOU as the computer will snap out of it in 2 turns and won't hurt itself once. Confuse Ray make it worse: it's 100% accurate, and pretty much every trainer with a Zubat, Golbat, or Crobat has this attack on it, and will be more than happy to use it on their first turn.
 * In Gen. I, anything with Poison Sting. The AI has an irritatingly high chance of poisoning you if you don't KO the opposing 'mon within a couple turns, sending you straight back to the nearest Pokemon Center.
 * Double Team. There's a reason why it's almost universally hated, and if there are any moves that people agree to ban from a battle, that one's right at the top of the list. Worst of all, the AI gives that move out to their Pokemon like Halloween candy and it has a tendency to make even your 100% accurate moves miss after just one use.
 * Protect, while not nearly as bad as the others, is still really annoying and makes you waste a turn and PP. If the AI at least used it strategically it'd be one thing (since you could still counter it with the attack Feint), but since it's purely AI Roulette they end up using it just because, even when it's obvious that you've already won and it won't help them thus they just delay the inevitable. The problem is that no one in their right mind would run a moveset with Feint on it, especially with the nerf. It now deals 30 damage (at least before, the damage of 50 could be bumped up to 75 with Technician), but now, even if you factor in a STAB and Technician, you aren't going to be busting 70 power with it. Meanwhile, its only use is to defeat Protect and Detect, both of which are not worth the trouble. Shadow Force, the only other attack that can counter Protect, is only available on Giratina, so if you don't use legendaries, good luck.
 * Watchog used Retaliate!
 * In multi-player games where items are allowed to be used, a Nidoking can easily turn into one of these back in Gen. I. One-hit KO moves have an accuracy of 55 (roughly 45%) in the game. X Accuracy doubles that. NIDOKING used FISSURE! It's a one-hit KO! Repeat four more times, and you will still have six pokemon to one when you lose all PP.
 * The evil storyline of Champions Return to Arms has Mithaniel Marr as the Final Boss. 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 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.
 * 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. 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 Mother 3, 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 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 or killed. Missed the Sea Pendant at the far end of the Lost Underworld? You're in trouble.
 * Made even worse when uses it. If Ness has a Star, Sea, or Night 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 or paralysis. Against a Duel Boss, that's a very bad thing.
 * In Mega Man X Command Mission, Ninetails has an attack called Nine Fragments. It deals out a fixed 999 damage NINE TIMES IN A ROW. There is absolutely no way to survive if it hits (unless you're 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 HP to One attack that never misses (unless it targets Stealth Mode Axl). Epsilon will open the fight with this move, and he spams it after he Turns Red. 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, making even Thunder - his weakness, what he's supposed to take more damage from - do minimal damage to him. It also allows him to use Pressure Abyss, an Ice attack that is always a Critical Hit.
 * Bass from Mega Man Battle Network 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, does not provoke Mercy Invincibility, 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 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.
 * Speaking of Liberations attacks, Dark Cloud. 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.
 * Players of Yggdra Union often cringe when the word 'Genocide' is mentioned. It's the signature move of That One Boss 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. Oh, and did I mention that you have to face this guy quite a few times?
 * Players of Blaze Union may cringe when the word 'Jihad' 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.
 * On that note, Bonus Boss #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.
 * And speaking of Gloria Union, 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 players in City of Heroes 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.
 * Thresher maws in Mass Effect 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 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."
 * In Mass Effect 2 there are a lot more examples of this trope. There are the Scions, whose Shockwaves tear your shields to pieces and ignore cover. There are the 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 Harbinger himself, who's fond of using a Singularity attack that knocks you out of cover so he can bombard you with Warp blasts. And finally, there's the, who only has one attack but needs no other, which is an energy beam fired from the mouth that devastates your shields and prevents them from recharging for a brief period of time.
 * It's not unheard of in World of Warcraft, 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 pray he doesn't target a any Squishy Wizard, 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 That One Boss, 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? 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, 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. Arguably 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.
 * In The Last Remnant, 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, guess which one of you will die from it.
 * Two bosses in Puzzle Quest 2 have literal One Hit KO 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.
 * Bonus Boss 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).
 * .hack 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. 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 .hack GU, 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 Alpha. 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 Beta phase.
 * Orjugan, That One Boss of Ys VI: The Ark of Napishtim, has a deadly Wave Motion Gun style laser blast, which is difficult to dodge without also getting hit by his Combat Tentacles, which can kill you in one hit on Hard and Nightmare difficulties.
 * There are more than one here, but the Megiddo technique from Phantasy Star IV 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.
 * Breath of Fire: Dragon Quarter has Malefactor, used by . What it does is afflict 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 Seiken Densetsu 3, 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 dead. If two of these are used on you in a row, you're just screwed. And keep in mind, these are attacks done by normal enemies.
 * Enchanted Arms 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 absolutely anything in the game. Yes, including the final boss.
 * The spell Abi-Dalzim's Horrid Wilting in Baldur's Gate 2. 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 Squishy Wizard 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).
 * Everything used by Sirius in Mega Man Star Force 3. Satellite Blazer, his signature attack, hits every tile of the field and can't be blocked (or dodged for that matter, unless you have Air Shoes). Another favorite move of his is Wing Formation, in which he detaches his wings, which start shooting elemental lasers. He has four wings, so one column of the field will invariably have a double-element attack going on. Again, unblockable and also unavoidable; the only real way to survive this move is to keep getting in columns that don't knock you out of a Noise.
 * The final boss of Skies of Arcadia 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 One-Hit Kill of your Squishy Wizard, 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; no such luck for Blue Winds.
 * Flash game 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 Marathon Boss without this attack. With it, he becomes That One Boss. The only saving grace is he likes to use it on himself if you last long enough.
 * The Etrian Odyssey games are liberally sprinkled with these, as you'd expect from a game this Nintendo Hard.
 * Any attack that hits the whole party for multiple status ailments.
 * 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.
 * Trickster Online 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 Xenoblade Chronicles, Jade Face/'s Laser Cannon 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.
 * Monster Girl Quest Paradox has many of these. However, some of them can also be learned by your party members as well.
 * Monster Lord's Cruelty does massive damage to the whole party, is dark elemental (so it can't be evaded or reflected), hits multiple times (so Endure won't save you) and, as if that wasn't enough, each hit has a chance of inflicting Instant Death. This attack is one of the main reasons why Alipheese the 16th and Black Alice are so tough.
 * Disruptive Wave, which removes buffs from the entire party. Players of Dragon Quest (which has an identical move) will be familiar with how frustrating this is.
 * Chaos Drive stops time for everyone but the caster. This doesn't just stop the party from acting, it also prevents evasion and effects that trigger in response to something. On the other hand, characters with a passive ability that makes them take action at the end of a turn will stop the Chaos Drive to do so (presumably a bug).
 * The PSP adaptation of Digimon Adventure:
 * Digimon with skills that can potentially inflict "unconsciousness", like Phantomon.
 * Basically any boss packing status buff skills like Anger, Fighting Spirit, or Focus. In this game, status buffs, while limited up to two stages, can give significant boost. They can easily turn the tide of battle, especially during late-game. The inverse is also true, as status debuff skills can cripple your Digimon. It's even worse if an enemy Digimon happens to combine both.