Dashie: Ok, I'm gonna pick, I'm gonna pick Liu Kang—
[Kung Lao's hat chops off Geras's head]
Dashie: —What?! Hold up, it didn't even say "finish him" or nothing! He just did a fatality like that? That's against the rules!
Two characters are getting ready to fight each other. They might have any weapon you could think of, supernatural powers, or just Good Old Fisticuffs. One of them decides to finish the fight as soon as it begins and unleashes their strongest attack on their opponent.
This is when a character uses the strongest attack they know against their opponent at the beginning of a fight, which either results in the victim being outright destroyed, the striker painfully realizing that this opponent is much more powerful or, in rare instances, the victim taking the loss to lower the striker's guard for a later encounter.
In Anime, this is either one of the coolest things you'll ever see or an Epic Failure to kill the opponent. The latter case might be one of the most hilarious parts of the show... unless it's Played for Drama. Video Games can have this if the player saves their best attack for an incoming boss battle, and then uses it straight away; an enemy might also use this tactic, in which case it often overlaps with Press X to Not Die. In Professional Wrestling, this is referred to as a Squash Match.
May be combined with Deliberately Jumping the Gun to really up the effect.
Compare and contrast the Single-Stroke Battle, in which the decisive blow needn't be an especially powerful attack; Rocket-Tag Gameplay, a gameplay trope where characters' offensive powers are so great that any fight is either this trope or a No-Sell; and Curb-Stomp Battle, where the opponent doesn't really need to use their best attack all the time to kick someone out of the atmosphere.
See also Alpha Strike and Death-or-Glory Attack, which needn't be the first attack; and HP to 1, which doesn't quite finish off the opponent on its own. Related to The Worf Effect and The Worf Barrage. No-Sell is what happens when any attack completely fails to work on the other guy.
- Lyrical Nanoha:
- Forbidden by the mechanics of Functional Magic for the title character: her most powerful Signature Move only works after a considerable number of magical attacks have already been exchanged in the airspace, for the simple reason that it feeds on the magical energy that lingers in the area from said attacks.
- Defied more explicitly in the Magical Girl Lyrical Nanoha Striker S manga bonus chapter: the starting distance between Nanoha and Signum in a mock battle is chosen so that neither can effectively use their respective One-Hit KO moves (long-ranged and close-ranged, respectively).
- In One-Punch Man, Genos immediately resorts to incinerating the entire House of Evolution with his cannons rather than go inside. Unfortunately, the most important parts of the facility are underground.
- Most of Kenshiro's Hokuto Shinken arsenal in Fist of the North Star is composed of killing moves, meaning that this is more often than not the default for him.
- Yu-Gi-Oh! likes to do this by having a character bring out their strongest card or some kind of game-winning combo as their opening play. Needless to say, this generally means that they are either going to win that turn, or that they are going to lose their strongest card (and possibly the duel) on that same turn.
- In the original series, Ryuzaki and Haga bring out their two best cards, Insect Queen and Black Tyranno, on their first turns. They then get outdone at their jobs by Siegfried von Schroeder, who wins the game on the following turn.
- Prince Ojin versus Saiou in Yu-Gi-Oh! GX: Ojin brought out his main card, Satellite Cannon, and used a combo to boost its ATK considerably and enable it to attack, which would clinch him the win on his first turn. Needless to say, not only did Saiou block the attack, but he used it to activate a combo of his own that redirected Satellite Cannon's attack to Ojin—winning the game before his first turn.
- Also in GX, Doctor Collector versus DD. The Doctor uses a clever combo involving banishment-based cards to bring out five strong Spellcasters on his first turn, creating a field that will block all attacks, give him a sizeable amount of offense, and burn the opponent considerably with each turn, complete with a strong Trap for insurance. DD brings out Plasma—we don't see the resolution, but it's clear he won immediately after. We get another taste of this when Edo fights DD: Edo brings out his own ace monster, Dogma, which is immediately consumed by Plasma on the next turn, showing he'll be in for a rough match.
- Spider-Geddon: Invoked by the Superior Spider-Man, who tells Takuya Yamashiro that he should just use his finishing move, Sword Vigor, right at the get-go. Takuya protests that doing so would be dishonorable, but does so anyway to kill Solus and pay him back for having destroyed Leopardon in Spider-Verse.
- In the Dragon Ball Z Abridged related "Cell vs." videos (where Big Bad Cell is challenged by various anime and video game characters in the week leading up to his duel with Goku to decide the fate of the world), Ken Masters from Street Fighter attempts to pull this when he fights Cell. As soon as the bout begins, Ken launches into his super combo... and due to the unimaginable difference in power (Ken is barely above a Badass Normal on the Dragon Ball Z power scale, while Cell is a nigh-immortal Physical God who can blow up planets without even trying) Cell effortlessly parries every blow as soon as Ken goes to throw it. And then turns Ken into A Twinkle in the Sky with a punch that is probably a love tap for Cell.
- Guardians of the Galaxy: When the Guardians confront Big Bad Ronan on his flagship, they immediately hit him with a missile from a BFG said to be capable of destroying moons. He emerges from the Smoke Shield completely unscathed, forcing them to use more creative measures.
- Iron Man 2:
- Rhodey points out that Tony should have used his deadly laser attack at the beginning of the battle. Tony's response is he was saving them, since they're one-time use only.
- A moment later, when Vanko arrives, Rhodey decides to use his most powerful weapon immediately: the bunker buster missile "the Ex-Wife". It completely fails, bouncing off without exploding.
- Defied in Soldier after Captain Church says they should just Nuke 'em from Orbit. "My daddy always said, 'When you want to insert a nail into a piece of wood, don't do anything fancy or glamorous. Just take the damn hammer and hit the son of a bitch until it's in.'" He's overruled by a pompous Colonel who wants to use his new genetically modified soldiers, which leads to the deaths of the soldiers, the Colonel, and the Captain.
- In The Archonate novel Majestrum, we see a flashback to a wizards' duel where one combatant begins by attacking with everything he's got, and doesn't have the slightest effect.
- Ender's Game: This is Ender's primary philosophy when it comes to fighting (and warfare): overwhelming shock and awe. Basically, thoroughly and savagely attack your enemy to the point where they never attempt any kind of retaliation out of outright fear.
- Happens near the very beginning of the novel, when he's being picked on by bullies. He knows that they'll never leave him alone if he just takes their abuse, so he brutally beats (and, unbeknownst to him at the time, kills) the leader of the gang to intimidate the rest of the group.
- In the Battle School, when he's confronted by a gang in the showers. He goads the leader into fighting him one-on-one, then proceeds to once again brutally defeat him. After that he gets a reputation as someone not to be messed with...
- And finally, at the end of the book when he's leading the fighters in the simulation, he instructs a fighter to, instead of engaging the enemy fleet directly, to bypass it completely and just directly destroy the home planet of the enemy. Works better than expected...until it turns out it wasn't a simulation at all, but a real-time feed to the actual, real battle, and Ender just committed genocide against the alien race. Oops.
- Harry Potter: Despite having plenty of other powerful spells up his sleeve, the Big Bad Lord Voldemort usually just fires a Killing Curse at anyone who dares oppose him.
- In the science-fiction short story "A Rose for Ecclesiastes", the hero has to fight a much larger opponent who is also a trained-from-birth warrior monk. The hero puts everything into a single Death-or-Glory Attack, which fortunately works.
- The Courtship of Princess Leia: Early in his efforts to restore the Jedi Order, Luke Skywalker faces off against Gethzerion, a powerful Dark Side user who, unlike the Empire, has no interest in capturing or turning him. She immediately gives him a massive brain aneurysm and leaves him for dead.
- The Wheel of Time:
- Moiraine is a powerful, talented, and versatile member of the Aes Sedai Magical Society, who uses a wide range of combat spells. The instant she sees one of The Dreaded Forsaken, she opens with the Dangerous Forbidden Technique of Balefire and utterly annihilates him.
- Most of Rand's fights against the Forsaken involve tactical strikes and/or protracted Wizard Duels. When he locates Graendal, however, he drops a Fantastic Nuke on her stronghold without further ado. She teleports away by the skin of her teeth.
- In Hikonin Sentai Akibaranger, the Akibarangers use this tactic in their first Monster of the Week battle. The monster's Mooks end up Taking the Bullet for him and he criticizes the Akibarangers for resorting to a cheap move early on.
- In the finale of Power Rangers Turbo, they use their finishing move to open the fight with the Monster of the Week. It doesn't work and they wind up losing all their Zords in the ensuing battle.
- In Video Game Championship Wrestling, the match between Sans and Monokuma at Killscreen V began this way, with Sans interrupting Monokuma's monologue by using every single one of his signature and finishing moves in rapid succession.
Sans: always wondered why people never use their finisher first.
- The combat system introduced in the third edition of Exalted can make this a fully-viable option, though not without risk. A Dawn Caste Solar who does well on their Join Battle roll could opening with Thunderbolt Attack Prana (a Charm that both lets you close the gap to your opponent and then double the damage on a decisive attack) and a bunch of combat Charms and either kill their target outright or leave them so badly injured that their wound penalties will leave them on the defensive for the rest of the fight. Or they'll miss with the attack, waste the Essence they used to fuel it, and lose a chunk of initiative because they missed a decisive attack.
- Breath of Fire: Dragon Quarter: After unlocking Ryu's D-Dive, it's possible to go dragon mode on the first turn and annihilate any enemy with his D-Breath... but doing so isn't recommended since if Ryu's D-Counter reaches 100% it's game-over.
- Chrono Trigger: Big Bad Lavos' first form always uses "Destruction rains from the heavens!" (a Herd-Hitting Attack) as its first move.
- In Dark Elf Historia, Vanessa usually uses all of her strongest magical attacks first, for all the good it does — by the time you fight her, you're likely to be too powerful for her to be defeated by a handful of magical attacks.
- Divinity: Original Sin II: The insane, undead witch Alice Alisceon can't be reasoned with and begins combat with a devastating firestorm that can wipe out a closely grouped party in one hit. It's an immensely difficult fight compared to the rest of her quest, but at least the ability has a long Cooldown.
- The Elder Scrolls IV: Oblivion: Initial Evil Gloating notwithstanding, the Necromancer Mannimarco opens the fight against the Player Character with a spell that would instantly kill and reanimate them. Fortunately, the previous quest wins the character an artifact that No-Sells the effect.
- Fate/Grand Order:
- There are a number of equippable "Craft Essences" for your Servants that give them a number of Noble Phantasm charge at the start of each battle; during the beginning of the battle you can also activate skills that give a certain Servant some NP charge, so that when they enter attack phase, their Noble Phantasm will be available at the first turn. Using this strategy is key to quick farming, as well as dealing a lot of damage on bosses in the first turn.
- The Final Boss for Part 1 opens the fight with his Noble Phantasm, which is so strong that your frontline Servants are likely to die right away. Before the attack he uses a buff (among others) that makes his attacks pierce invincibility unless you use a "skill sealing" skill on him beforehand. Even then, you still need a invincibility/evasion buff (or hefty amount of attack debuffing/defense buff) to survive it.
- In Final Fantasy X, characters build up Overdrive as they fight, to be released in a big, flashy attack. However, since Overdrive stays banked after a fight ends, it's a common tactic to raise it to max fighting Mooks before you go up against a boss. And against some bosses with an annoying initial form, blasting the Overdrive immediately can be the best strategy.
- Happens offscreen in Fire Emblem: Three Houses. Ferdinand fancies himself The Rival to Edelgard, who is the heir to the throne of the Empire. They fight a duel upon reaching a B-Support ranking, and Ferdinand is stunned and dismayed that Edelgard defeats him almost immediately. She responds that she felt she had to use her best techniques right out the gate, because while Ferdinand was overconfident and too inexperienced to know what a real duel was like, he was also too good a fighter for her to take any chances.
- Golden Sun: By holding enough un-equipped Djinn, a character can unleash a powerful Summon attack, at the cost of those Djinn becoming unusable for several turns. An effective strategy for bosses throughout the series, up to and including Bonus Bosses, is to un-equip all the party's Djinn before the battle and fire off every Summon available to take the boss down on the first turn. (However, since equipped Djinn provide stat boosts and abilities, any boss that isn't overwhelmed by the Summon barrage can easily take down the weakened party - and the final bosses of each game have multiple stages specifically to block this strategy.)
- In Heroes of Might and Magic, the Armageddon spell is meant to be a Rage Quit mechanic, where you use an über-powerful spell that completely deals massive damage both your and your enemy's armies in the case of an unwinnable scenario. However, if you take along a creature that's immune to fire magic (e.g., Efreets, Fire/Earth Elementals, Phoenixes) or a creature that's immune to magic in general (e.g., Black/Gold Dragons, Magic Elementals, Battle Dwarves) you can nuke your enemy's army at the start of a battle without losing any of your own.
- Honkai Impact 3rd:
- Lightning Empress (one of Mei's battlesuits) has a passive skill where, if she's set as the leader on a team, she'll give her whole team 50/60/70 SP (depending on her suit's rank) at the start of the battle, letting the team use their Ultimate Skill sooner (especially if the team's members have Ultimate Skills that use 50 SP or less).
- In Coop Multiplayer, Valkyrie Bladestrike (one of Mei's battlesuits)' Team Skill is to fill SP for the whole team the more they have done hits in their combos; this can be done at the start of a battle, letting them use their Ultimate Skills sooner. Valkyrie Chariot (one of Bronya's battlesuits)' Team Skill is to create a small Area of Effect that quickly fills the team's SP when they stand in it; this can also be done at the start of the battle. Valkyrie Chariot herself also has an Ultimate Skill that gathers enemies around with only 50 SP, so that beginning team stages with her Ultimate Skill (especially when there are a lot of enemies around) would greatly help with finishing the stage faster.
- The QS and Dirac Sea modes automatically set the starting SP of all your Valkyries to 90 at the start of every fight, regardless of how much you were above or below 90 in the previous encounter. Needless to say, most Valkyries can either use their Ultimate Skill immediately or are close enough that they can gather the remaining SP to do so not long after the battle starts.
- In The Legend of Zelda: Twilight Princess, the most powerful attack Link can learn is the Mortal Draw, which does critical damage while drawing the sword. Against unarmored foes, it can end a battle as soon as it begins.
- Mortal Kombat 11: Chapter 3 of the Story Mode has Liu Kang and Kung Lao face off against Geras, who is stealing from the Jinsei (the life energy of Earthrealm). When Geras states that Kronika intends to use it to remake history, Kung Lao responds by throwing his hat at him, chopping his head off, and catching it, complete with him wiping his hat off with two fingers and smirking.
- Mike Tyson (or Mr Dream) infamously opens his fight in Punch-Out!! with his most powerful attack: 90 seconds of nothing but One-Hit Kill uppercuts. If you avoid them all, he'll switch to fighting you more traditionally, but he'll still pepper in the uppercut.
- Shin Megami Tensei III: Nocturne: The failure variant is used in one Boss Battle. The spectre begins the fight by attempting to cast a powerful Megido spell, which fizzles out since it doesn't have the Mana reserves to cast it. For the rest of the fight, it uses Mana Drain spells on your party until it has enough mana stockpiled to cast it properly.
- Speaking of ATLUS games, Persona 3 and Persona 4 have their strongest Bonus Bosses periodically cast a Megidolaon that will do 9999 damage to the party in a game where the HP cap is 999. However, if you start the battle breaking one of the unwritten rules, the very first action they'll take is this very One-Hit Kill attack. Even if you use a method to avoid dying to it, the boss will simply keep spamming it until you die, and you cannot escape your dues forever.
- The Bonus Boss of Part 1 of Digital Devil Saga, the above-mentioned Nocturne's main character, works along similar lines to his counterparts in Persona. This guy takes it a little bit further though: if you start his battle breaking one of his rules, you won't even get to see your battle menu open because this guy will immediately cast Gaea Rage as soon as everyone finishes spawning and deal (to the average player entering this fight without extensive Level Grinding done beforehand) over 10 000 damage in health to the entire party. If you did do massive amounts of Level Grinding, your party merely takes several thousand damage instead. Your HP cap is also 999. note
- Street Fighter:
- Dramatic Battle Mode in Street Fighter Alpha 2 (and Alpha 2 Gold) not only grants the player a full bar of meter right off the bat; it gives them (and their partner) infinite meter. Considering the final opponent in this mode is none other than Shin Akuma and fighters share a lifebar, this was probably the developers being merciful.
- Alpha 3 is the first game in the series where the fighters begin a 1-on-1 match with the Super Combo Gauge full (translating to 3 bars of super meter), which allows players to whip out a LEVEL 3 SUPER as their first move. This includes Akuma's Shun Goku Satsu.
- In Undertale, the final boss of the Genocide route, Sans, opens his fight by unleashing a huge barrage that's extreme even by the game's Bullet Hell standards. This is even more surprising since he also gets the first move in the fight, unlike every other enemy in the game.
"Huh. Always wondered why people never use their strongest attack first."
- Recommended by the Evil Overlord List: