History Main / PerfectPlayAI

* [[https://en.wikipedia.org/wiki/Solved_game Solved games]] allow for truly perfect play AI. For a game to be solved, it must have perfect information, a finite set of potential moves, and no random elements. More details on TheOtherWiki, but consider Tic-Tac-Toe. The first player (because of the symmetrical play space) has three choices for their first mark; side, corner, or center. Depending on their play, the second player has a very small number of possible moves in response. As a result, a human with scratch paper can map the entire space of possible Tic-Tac-Toe games and write a perfect algorithm to play it flawlessly. Such an algorithm will always draw against perfect play and never loses. A clever grade-schooler can memorize how to play Tic-Tac-Toe flawlessly.

!!Non-game examples:
* In ''Literature/SuperMinion'', Adder describes Tofu as always making the perfect move in every situation during a fight. This makes him a fearsome opponent for all but the most skilled opponents, but Adder knows exactly how to manipulate him because even reliably making the right choice [[AIBreaker is a kind of predictability]].

** Dark Link in ''VideoGame/TheLegendOfZeldaOcarinaOfTime'', being a ShoutOut to the original, mirrors Link's sword attacks (almost) perfectly, causing nothing more than clashing blades. (Dark Link is also opposite-handed from normal Link, adding to the 'mirror' effect) He backflips to counter Link's charged spin attack, and if the player attempts to make a thrust attack, counters by '''''jumping on Link's sword''''' and striking. For the first half of the battle he doesn't even attack at all, but merely stands back and counters Link's moves. But he actually doesn't counter much else, such as bombs or Deku Nuts.

* In ''Literature/SuperMinion'', Adder describes Tofu as always making the perfect move in every situation during a fight. This makes him a fearsome opponent for all but the most skilled opponents, but Adder knows exactly how to manipulate him because even reliably making the right choice [[AIBreaker is a kind of predictability]].

** The game Tic-Tac-Toe can be played perfectly by humans. Perfect play results in a draw. To understand perfect play, you could literally work out all possible games of Tic-Tac-Toe on some scratch paper, and if you do so, you can build a decision tree. Once you do, you realize you have a very simple game where players who know what they're doing will always end up in a draw. To start, realize X only has three initial plays; corner, side, or center. All corners and sides, after all, are equivalent at the start of the game.

* Not just limited to fighting games; does anybody remember the original Reaper bot for Quake? It can't read your input (for a 90's FPS, that wouldn't even make sense), but it could hear you from anywhere on the map, had dead perfect aim (emphasis on "dead"), a reaction time measured in milliseconds, and could dodge anything non-hitscan that you threw at it. Later shooters, and even later bots for Quake, deliberately nerfed their bots to be less inhuman (unless you played at the most masochistic difficulty levels, anyway).

** The game Tic-Tac-Toe can be played perfectly by humans. Perfect play results in a draw. To understand perfect play, you could literally work out all possible games of Tic-Tac-Toe on some scratch paper, and if you do so, you can build a decision tree. Once you do, you realize you have a very simple game where players who know what they're doing will always end up in a draw. To start, realize X only has three initial plays; corner, side, or center. All corners and sides, after all, are equivalent.

* In ''VideoGame/GuitarHero III'', Lou misses no notes for the most part (but read on), and often times throws attacks at you during your own attack phrases. Averted when you do get an attack and throw it at him, as he [[ArtificialStupidity completely falls apart]], even if the affected section could reasonably still be hit by a human player.

** ''Street Fighter Alpha 2'''s Shin Akuma on any setting and to a lesser extent ''SFA 3'' Akuma on medium and up are terrible about this. His PerfectPlayAI routine consists of walking psychic shoryukens combined with tick throws, the result being that you're afraid to poke with anything, because no matter what you poke with, or how you set it up, the comp will just read your buttons and DP you out of it. If you block, the computer will just tick throw you out of it. If you are expecting the tick and try to reverse the throw, you'll get psychic DP'ed (since you're performing a throw/attempt and not really blocking). Try to perform a reversal and you'll be thrown. Occasionally (and Ryu will do this as well, though not with all the other stuff Akuma adds in), if you get the reversal, Akuma will actually block, then throw a reversal DP on the tail end of yours.

* The FinalBoss of ''VideoGame/ZeldaIITheAdventureOfLink'' is an example that predates even the more infamous fighting (i.e. [=MK=]) examples: Dark Link aggressively advances toward the player and tries to attack whichever position (high or low) the player isn't currently guarding against; and when the player attacks, Dark Link merely counters with his shield in the appropriate position. He is remembered for having one flaw in his AI ("duck and stab") because he sometimes counters a low strike with a jump, which leaves his legs open to attack.

** If you set the difficulty to the hardest level on certain ''VideoGame/StreetFighterII'' games, nearly every character becomes a PerfectPlayAI. It's more proficient in Shotos and Guile, though, who especially like to jab faster than the speed of light. Also if you get caught in a hold throw, like Dhalsim's noogie or Balrog's head bash (that looks suspiciously like he's biting your ear), don't expect to escape anytime soon because they'll usually go faster than normal. Zangief is able to perform his most powerful move in a single frame even though it would take a human to rotate the joystick 360 degrees.

...right up until you run into a human opponent who knows what they're doing, and get [[CurbStompBattle completely destroyed]]. The chief problem with this AI behaviour is that it will absolutely wreck your reflexes or worse, knowledge of what works and what doesn't; once used to AI that's immune to fakeouts or any sort of coherent strategy, one that brutally punishes any sort of proactive play, you wind up forced into a purely reactive playstyle that will usually get you, as the parlance goes, [[CurbStompBattle bodied]].

* ''Franchise/MortalKombat'' is famous for this, and is why the trope used to be called the "MK Walker"; an AI opponent on this mode would simply walk over to the player, blocking or dodging any attack with inhuman frame precision and, upon reaching said player, execute a perfectly-timed, unblockable move (usually a throw). Hence "MK Walker".
** Basically all ''VideoGame/MortalKombat2'' characters at hardest setting.
*** Ironically averted on the UsefulNotes/PlayStation port where the AI is very stupid. There's a reason [[NoExportForYou it was only released in Japan]].

** ''VideoGame/MortalKombat3'' on the UsefulNotes/GameBoy has it too, but in this case the Walkers are surprisingly vulnerable to uppercuts. [[BrokenRecord Hope you enjoy doing nothing but uppercuts]].
** Shang Tsung can be murder for this; sometimes, in a single motion, the CPU will transform into a new character and perform the counter-attack that character knows.
** Jade in ''Ultimate Mortal Kombat 3'' deserves a special mention. When you play as her, the projectile protection special has to be activated by Back > Forward > High Kick command. When AI plays as her, if you try a projectile attack on her, most of the time she will activate the special at the exact moment you input the projectile move, [[TheComputerIsACheatingBastard while running towards you and without stopping at all]], and then rip you a new one before you can block anything.
** Smoke in ''Ultimate Mortal Kombat 3'' is impossible even on Very Easy. If you send a long range attack or projectile towards him, he will instantly teleport uppercut you INFINITELY. Before there's even an animation, he's already killed you. When you play as Smoke, the computer instantly dodges teleporting moves.
* ANY character from Kagemaru on in ''VideoGame/VirtuaFighter 2''.

* ''StreetFighter'''s Zangief, who will perform his trademark Spinning Piledriver in a single frame, every time he has the chance. The move in question [[ComputersAreFast requires a full circle]] ''at least''.
** In fact, this is ''specifically'' the reason why Zangief is a "villain" in ''Disney/WreckItRalph'': he frustrated scriptwriter Phil Johnson, an avid fan of Street Fighter II, as a kid to the point of being a ''meta villain'':
--> '''Phil Johnson:''' "That’s all my fault. I played a lot of Street Fighter as a young man and Zangief tormented me so much that I don’t care what anybody says, he was bad to me."
** If you set the difficulty to the hardest level on certain ''VideoGame/StreetFighterII'' games, nearly every character becomes a PerfectPlayAI. It's more proficient in Shotos and Guile, though, who especially like to jab faster than the speed of light. Also if you get caught in a hold throw, like Dhalsim's noogie or Balrog's head bash (that looks suspiciously like he's biting your ear), don't expect to escape anytime soon because they'll usually go faster than normal.
** ''SFA 2'''s Shin Akuma on any setting and to a lesser extent ''SFA 3'' Akuma on medium and up are terrible about this. His PerfectPlayAI routine consists of walking psychic shoryukens combined with tick throws, the result being that you're afraid to poke with anything, because no matter what you poke with, or how you set it up, the comp will just read your buttons and DP you out of it. If you block, the computer will just tick throw you out of it. If you are expecting the tick and try to reverse the throw, you'll get psychic DP'ed (since you're performing a throw/attempt and not really blocking). Try to perform a reversal and you'll be thrown. Occasionally (and Ryu will do this as well, though not with all the other stuff Akuma adds in), if you get the reversal, Akuma will actually block, then throw a reversal DP on the tail end of yours.
** Speaking of the Alpha series, friggin Final Bison in Alpha 3. With or without Final Psycho Crusher he's still incredibly annoying with this.
*** Let's not forget about Akuma/Gouki from ''Super Street Fighter II X''/''Super Turbo''. On eight stars he becomes the cosmic overlord of this trope.

** ''Street Fighter Mugen'''s Ryu. Enough said.
*** The CPU does cheat in many games. In fighting games you generally get 30-60 frames per second, and you get 1 input per frame. So a move like a fireball which is down, down forward, forward + attack would be 3 frames at the absolute fastest, which is really only achievable by the fastest players using a hitbox (which is a fighting controller with all buttons) consistently. The computer can do all moves in 1 frame without jumping or anything else for 360 motions. So if you drop a 1 frame link (a combo you must hit at the right time with 1/60th of a second interval) the computer will counter with a super move IMMEDIATELY, when it should take 6 frames or more depending on the move. The cheating part is not the input duration (the input could, in theory, be buffered during the combo, then the button pressed as soon as the combo dropped), it is the fact that the AI will notice the instant you drop the combo. However, in theory, one could simply be mashing the input out.

* It's back with a vengeance in ''VideoGame/SoulCalibur 5''. The AI has no problem executing just guards(which block practically any attack but require insane timing)at any time, can pull off Ivy's [[SomeDexterityRequired notoriously difficult]] Calamity Symphony throw at the drop of a hat, and can make grown men weep when controlling Alpha Patroklos( who is easily the hardest character to use, once again due to the ridiculous timing he requires, [[DifficultButAwesome but when mastered...]]).

* The old ''[[Manga/OnePiece One Piece: Grand Battle]]'' series of games on the Gamecube and UsefulNotes/PlayStation2, mostly the final one which was released only in America: ''Grand Adventure''. The opponent AI is actually pretty dumb on normal and hard difficulty, but ''hardest''? Hoo boy. You might as well be playing with a handicap against you; the AI no longer gets stunned when caught in a combo, (so they can attack you between punches, meaning slow MightyGlacier characters are next to useless) they're programmed to ''immediately'' grab or use a guard breaker the second you press the block button, and the ones with counter attacks will use them perfectly without fail. What's worse is that, unlike most fighting games, they often will outright have double your health, strength, ''and'' defense even when it defies common sense. The only way to win is to spam aerial attacks, items, and super attacks and hope you don't die (though ''throwing'' items no longer works either, since they have perfect timing and will catch them no matter what position they're in and throw it back at you).

* Unlock the 'Z3' difficulty in VideoGame/DragonBallZBudokai and ''every'' enemy in the story becomes this.

** ''VideoGame/MortalKombat3'' on the GameBoy has it too, but in this case the Walkers are surprisingly vulnerable to uppercuts. [[BrokenRecord Hope you enjoy doing nothing but uppercuts]].

* Every opponent on every difficulty in ''VideoGame/Facebreaker''.

* MortalKombat is famous for this, and is why the trope used to be called the "MK Walker"; an AI opponent on this mode would simply walk over to the player, blocking or dodging any attack with inhuman frame precision and, upon reaching said player, execute a perfectly-timed, unblockable move (usually a throw). Hence "MK Walker".

Perfect Play A.I. is a type of VideoGame AI most commonly found in {{Fighting Game}}s that correctly blocks or evades every attack and move the player is capable of performing against it, while slowly approaching the player to attack (often backing the player into a literal corner in the process). They were first popularized by the ''Franchise/MortalKombat'' series, but have become a recurring AI type in other fighting games, which are often so NintendoHard that it seems unfair (even when the computer is not [[TheComputerIsACheatingBastard actually cheating]]), possibly even [[{{Unwinnable}} invincible]].

* Real Life example: In ''Literature/TheArtOfWar'', Creator/SunTzu recommends "safe" approaches such as these in the following quote.

* Vergil from ''Franchise/DevilMayCry 3'' is close to, but not a true PerfectPlayAI. He will parry and counter your attacks, but you can dodge and counter his attacks.
* ''Franchise/DevilMayCry 4'' has a number of examples:

* Similar to the ''Zorba'' example above, ''VideoGame/{{Yakuza 0}}'' has a disco dancing minigame where the player can engage in dance-offs with other dancers. One opponent for these is Miracle Johnson, an {{Expy}} of Music/MichaelJackson, and the dance-off is set to a song [[SuspiciouslySimilarSong suspiciously similar to "Bad".]] Needless to say, Miracle will always get the highest possible score and [[HopelessBossFight there's no way to beat him.]]

Perfect Play A.I. is a type of VideoGame AI most commonly found in [[FightingGame Fighting Games]] that correctly blocks or evades every attack and move the player is capable of performing against it, while slowly approaching the player to attack (often backing the player into a literal corner in the process). They were first popularized by the MortalKombat series, but have become a recurring AI type in other fighting games, which are often so NintendoHard that it seems unfair (even when the computer is not [[TheComputerIsACheatingBastard actually cheating]]), possibly even [[{{Unwinnable}} invincible]].