AI Breaker

Subtrope of Fake Skill and Game Breaker, an action or a sequence of actions that exploits flaws in the game's artificial intelligence.

Either the programmers didn't consider the possibility of the player doing this, couldn't come up with an effective counter or there's a bug in the system that makes it perform in ways not intended. Ultimately, even if the AI does always respond in the "best possible" way to an action, it may still become an AI Breaker by making the opponent(s) too predictable.

Often the only way to beat a Perfect Play AI or SNK Boss, or any computer player that is overly skilled or cheap. Easily leads to Gameplay Derailment.


 * Soul Calibur 3's anti AI move are moves the AI rarely blocks or dodges, allowing the player to be the one to Mortal Kombat walk over the AI for once. Two of the easier to perform are Xianghua's Great Wall and Iron Sword/Strife's A+ B. Because The AI Is a Cheating Bastard itself, this is completely fair.
 * The thief/Chester's bomb throw, B+K, can be charged and rolled. If you charge and roll the bombs, the enemy will more likely than not block it, and if you quickly charge another roll right after the first they will get up to guard normally and get hit in the feet, as the computer can't skip the frame from getting upright to blocking low. Another easy one is staff/Lynett's front A+B, if you do it right then you can knock the enemy down and then keep pointing at them as they get up, as they will guard but the attack breaks the guards.
 * A really neat trick in Soul Calibur 4 involves the final, topmost floor of the Tower of Lost Souls, where you face a severely souped-up version of the game's final boss... who can, however, easily be defeated by letting him knock you over, and then roll yourself on the floor so you're between him and the edge. He'll then do a jump over you--straight off the edge of the tower, plunging to his death. By far the fastest way to make money in the game...
 * Sadly, this has been patched. However, throwing is once again an anti-AI move (it worked well in the second game), and thankfully it works against him. You see, no matter how high an opponent's defense is (theoretically, the final boss's defense is as high as it will go), throws always deal full damage. Plus, the computer doesn't grapple break as often as it did in the third game.
 * In Soul Calibur 4, using Yoshimitsu's Bullet Cutter attack will break the AI. The Bullet Cutter can be held, which will turn it from a normal attack into an unblockable attack. The response of the AI will be to block until it reaches its unblockable state, then try to attack. By releasing it shortly after it becomes unblockable and then quickly starting it up again, it's possible (and usually quite easy) to beat even the hardest AI without them landing a scratch on you.
 * In Wii Sports's boxing, the player can literally get their rank off the chart (and if they go at it long enough, off the screen!) by simply weaving back and forth, then countering when the AI throws a punch. A human player can just aim where you are going to be.
 * In Sacrifice's skirmish mode, the AI never uses the low-level but powerful Teleport spell, giving human players an enormous advantage.
 * In Metal Gear Solid 2 Sons of Liberty, when fighting the Harrier, you can't protect yourself from its missiles by hiding behind objects, because the missiles will always hit the object, and its explosion passes through the object and hits you. However, if you press yourself up against the object, the AI will think you're trying to move in that direction, and the missiles will always come in too low to hit you. May be the only way to beat it on Extreme.
 * In Metal Gear, the original, during the boss fight against Big Boss. He always tries to be on the opposite side of the room to you, so if you stand in the middle of the room, he gets confused and runs back and forth in one of the corners until you move. You can use this exploit to force him to run over your mines.
 * The original Metal Gear Solid is full of them. All of these examples and more are demonstrated in a mostly finished tool-assisted speedrun of the game, done by theenglishman.
 * Vulcan Raven sometimes fails to notice that he's knocked over one of the crates, but the collision detection keeps track. You can lure him into shooting one down, and then watch him walk into it repeatedly until he's provided with some other stimulus, like seeing you. If you hide in the corner, you can flatten him with Nikita missiles without him moving from his spot. He also has a slight overlap in his cone of vision and his minigun's hit radius, meaning that he can theoretically be whaling on a wall while you stand behind a wall and Nikita spam.
 * During the second phase of the Hind D fight (after the first major air strike) standing underneath the Hind will cause Liquid to be unable to see you, and you can spam Stingers underneath him while he strafes back and forth looking for you.
 * Guards will have a temporary moment of blindness after finishing their search of a suspicious noise, allowing you to take them out early.
 * It's possible, with very precise timing, to interrupt Ocelot's initial attack animation so that he enters a state where every single shot of his will miss as long as you keep firing at him.
 * And, of course, the infamous Infinite Combo, which can leave an enemy, with proper timing, in a constant state of recoil, allowing you to whale away as long as you keep the rhythm.
 * In The Elder Scrolls: III Morrowind, the NPC-controlling AI does not know how to use levitation spells. It's possible to cast levitation on NPCs, but they just do not know what to do then. So you can fly a bit off ground and most enemies will not get you there... except cliff racers, who naturally fly.
 * The Elder Scrolls IV: Oblivion features the same AI problem as Morrowind, even though levitation spells were removed - if you stand in an area which enemies can't access (say, by jumping onto a large rock), they'll just run back and forth a little while you pelt them with fireballs and arrows. Oblivion also suffers from AI stupidity with invisibility (which wears off when you attack, but immediately makes everyone forget you exist if you recast it) or 100% chameleon (which makes enemies completely oblivious, even if you smack in the head repeatedly with a huge axe).
 * The odd thing is that if you have full 100% chameleon armor on all the time, this becomes such a Game Breaker that the game becomes a breeze. You never, ever get attacked unless there is a script, as long as all the armor is on, and even enemies that are scripted to attack you won't see you. You can run around, smack guards and steal all day long and aside from the guard talking to you, they won't even see it. You can just run up, punch a guard in the face, and he will do the whole "you broke the law" talk, and if you resist he pulls out his sword and says "Where did he go!?" It makes for some quite funny gameplay.
 * In Daggerfall, if you stand a certain distance from some enemies, they neither come closer to engage in melee nor draw their bow and snipe at you from that distance. They stand perfectly still and do nothing.
 * You can trick the AI into a lot of things in Super Smash Bros Brawl, but the most memorable trick is probably the 'Fly To Survive' scheme... only useable with the handful of characters who posess limited flight capabilities, and mostly useful for the Cruel Brawl survival-test, where you face a bunch of SERIOUSLY overpowered AI's... but by simple constantly flying UNDER the island the battle takes place on - hanging off the ledge on either side to reset your flight-time counter - you can trick the AI's into jumping off the screen with a little practice.
 * In the previous game, Melee, one famous enemy was Donkey Kong who had one tactic if the opponent stayed still on his stage. Charge, jump, jump, flip-hammer-punch. Unfortunately for him, his flip-hammer-punch disables his ability to hang on to edges, you spawn on a fairly small platform, and to properly hit you, he has to miss your platform by a bit, over one of the few levels in the game where you can't really recover from a fall--particularly since his timing puts him into the ground just when an instant death enemy jumps up to bite at people's heels...
 * In Melee, all you have to do to get easy wins is make your opponent a maximum-difficulty Roy, turn off items, play in Jungle Japes, KO Roy once, and stand on the far right side of the stage. He WILL fall to his death over and over and over again when he tries to go directly from the respawn platform to your platform and misses the jump.
 * You could also battle a Luigi in both of the Mushroom Kingdom stages. Luigi's AI has him use his Green Missile for recoveries, so spiking him into one of the small pits causes Luigi to use the move, hit the wall, and fall to his death.
 * Even easier, level nine Ness on Jungle Japes, 1 stock match. Do nothing. He jumps toward you, tries to recover, falls down the hole between your platform and the main one, hits the side of the stage with PK Thunder, continues to fall, and dies.
 * Even easier, just leave Ness at level 1. He will do the same thing, minus PK Thunder.
 * Also, on the original Smash Bros. you could defeat Pikachu on Story Mode without even touching him by just jumping around the tower on the right, causing Pikachu to quick attack himself off of the platform.
 * It's also possible to do something similar with Fox in the original Super Smash Brothers: stand near the nose of the Great Fox and wait for him to charge you, then jump over him. Fox will be unable to recover, and will either fall off the screen or land on the Great Fox's lasers, at which point it's only a matter of time before the lasers fire and he asplodes.
 * The 15-Minute Melee can be mostly beaten with just Donkey Kong's hand slap. The developers were probably aware of this; surviving for all 15 minutes unlocks the N64 Donkey Kong stage.
 * While it was helpful in the long run and probably anticipated (along with Fox/Falco's side-B) explosive items had a nasty tendency to drop where you were banging the ground, especially near the end...
 * CPU players can't cope with spikes, falling platforms or most custom stages, so one of the easiest ways to beat even the highest level opponents is simply to make your own level with those elements and just play on that.
 * Brawl's stage editor allows for all sorts of bizarre computer player behavior. For instance, if you create a square, open at the top, on the upper-right corner of the stage and it's the correct size, Lucas will spend the entire match jumping back and forth.
 * One of the SNES Madden NFL games had this problem: it is possible to use the same play for an entire season and the computer opponent could never figure out how to stop you.
 * Heck, all of the newest gen of Madden games have them. You can set "Hot Routes" for individual receivers before the play starts. Set your Tight End to run an "Out" or "Slant" pattern, and throw just after he cuts on the Out route or right after your Quarterback's dropback animation on the Slant. He'll be between the Outside Linebacker and the Cornerback and uncovered by either 9 out of 10 times, even on All-Madden difficulty.
 * Also, AI players set their contract demands based on their Overall rating. One common trick is to forcibly change their position to one they are terribly ill-suited for (WR -> DT, for example), so that their Overall rating takes a massive hit. Then re-sign them for peanuts and switch them back. You could even do this to opposing teams' players and get them to trade away their stars.
 * In NCAA 2011, pump-faking backwards would cause all the defenders to abandon their assignments and rush the QB, leaving your receivers completely uncovered downfield.
 * In Dragonball Z: Burst Limit, several of the hardest challenges can be overcome by spamming Vegeta's 'Final Flash' super-move... apparently, the AI considers it a 'super beam' attack, and duly sidesteps it -- only, the Final Flash is actually an Area of Effect cone, meaning that they step straight into it (instead of blocking, which would greatly reduce the damage). And because the AI considers dodging to be better than blocking, the higher the level of the AI is, the more likely it is to fall for this...
 * In Dragonball Z: Ultimate Tenkaichi, almost all AI opponents will become completely helpless if you stay directly above them at blast range, allowing you to bombard them with Ki Attacks at will. Most characters' shots can't hit straight up at all and the the few that can won't get too many hits in compared to you shooting down (although, some characters can't shoot down all that well, either). The AI is too stupid to fly up to you or run farther away to aim.
 * In Naruto Shippuden Ultimate Ninja Storm Generations, Itachi got a new move, Clone Jutsu: Super Explosion. What it does is create a clone of Itachi that walks forward veeeeeery sloooooowly and explodes when touched or attacked. A human player can easily just sidestep it, but for some reason the AI falls for it every time and walks, or even dashes right into it. This makes getting through Itachi's story laughably easy.
 * Rome: Total War: When defending a city, enemy troops will tend to congregate in the town square, which they're supposed to be defending. They will continue to stand there mindlessly under a hail of missiles from the adjacent streets, so long as none of your troops actually sets foot in the square itself.
 * Alternatively, you can run a cavalry unit into the town square, cause the enemy to chase after you, then leave the square. Repeat this until the enemy can barely walk before a full frontal onslaught. This actually works in any offensive battle where you out-power your opponent.
 * Before the first patch, a single group of town watch with a level 1 wall could easily beat any size of army that didn't have elephants or onagers. As soon as you get besieged (before they can build battering rams), sally out to meat them. Then, go out the gate opposite the army (you have a gate on each side of the town, N/S/E/W). The army will see that there is an open gate and run around the city, right by the towers. Then, go back inside. As soon as the gate closes and there is no units targetable, the army will stop where they are, regardless of whether or not they are being shot at by the towers. As only siege can target towers, they do not respond. Crank up time and watch their best units die one by one. After 15 minutes or so, the battle will end. Continue until their army is literally dead through stupidity.
 * In Bully, nobody can jump onto cars. You can actually stand on the hood of a car and pick off police officers with your slingshot. They may throw bricks at you, but that's it, they can't do the insta-defeat grab.
 * Descent 2 had enemy AI that worked in beats. So the best way of fighting mine robots was to work in counter-time, to move and fire in the split second before the next AI poll. It gave the game a rhythmic, dance-like quality.
 * Given their computational power and knowledge databases, defeating the most computer programs in Chess requires you to take advantage of these: defeating the best chess engines requires you to utilize anti-computer tactics and have a grandmaster level of skill in chess... but even then, a draw is considered impressive. Take a look at the Brains in Bahrain for an example of anti-computer play. Simpler chess programs usually have more easily exploitable weaknesses.
 * Some of the early versions of Mortal Kombat had a bug where you could simply continually walk backwards and sweep the opponent whenever he got too close, and win every match this way until you get to Goro. The later arcade versions, as well as the home versions, fixed this.
 * Also, Shang Tsung can be easily defeated by crouching and kicking out whenever he approaches.
 * Mortal Kombat 3, UMK3 and Mortal Kombat Trilogy all have the "hypnotic walk" glitch: if you are about jump distance from the AI, start to walk backwards and forwards alternately for a few steps. This causes the AI to copy your pattern, and as long as you keep it up, the AI will not do anything else. This allows players to beat the Perfect Play AI: once they managed to land a hit, they could exploit this glitch and continue to dazzle the AI until time runs out. This yields tedious but easy wins. Of course, landing a hit on a Perfect Play AI is tricky in the first place...
 * Mortal Kombat 9, too, has methods to break the AI: by using characters that can teleport, the player can easily figure out the AI's patterns and fool them into attacking thin air. This is very useful in the final battle of Story Mode (Raiden vs. Shao Kahn): when you teleport as Kahn is about to attack (or in the process of attacking, depending on how good your timing is), you'll reappear behind him, while he's open for a free hit. After he's hit, he'll immediately try to attack you head-on most of the time; just teleport behind him again and strike him before he can turn. It's a slow and steady win.
 * Dracula in Castlevania: Order of Ecclesia will abort whatever attack he's using and raise a wall of flame if you try to fly. This attack can be dodged if you move towards him while flying, so you can make him abort all his much more annoying regular attacks.
 * While most people consider Julius Belmont of Castlevania Aria of Sorrow to be That One Boss, you can easily beat him by double jumping and kicking him in the head repeatedly if you took the time to get the air kick ability soul from the Kicker Skeleton in the same area.
 * Astarte in Castlevania: Harmony of Despair (and possibly in her original game, Portrait of Ruin) will attack at whatever location you were last at, but thanks to the overall slowness of some of her attacks, the fact that she walks around slowly between attacks and she's human-sized and thus easily jumped over, you can just jump over any of her attacks, stand still until she finishes, jump over her again and watch her slowly march where you were and attack thin air. You can easily have her facing the wrong way for most of the battle, making her relatively easy to kill since she has no attacks that hit behind her besides her That One Attack Temptation. However, this does tend to bite you in the ass in multiplayer since there are more than 1 target for her to attack and you can't tell who she's aiming for unless the entire team manages to stay on one side of her.
 * The first NES Teenage Mutant Ninja Turtles game had a hilarious one with the foot soldiers; walk away from them at exactly the right moment as they jump at you, and they get confused and start hopping in place without attacking. Makes them rather easy to beat.
 * Not to mention being able to defeat Rocksteady by just attacking him from the top right with Donetello.
 * Even Shredder is not safe from this. Stand in correct spot when battle starts and he cannot touch you, while you can kill him at your leisure or even put controller down. Said spot is on bottom floor on 7th tile from left wall.
 * Fun fact about the guards in Assassin's Creed: those wild sword swings they make can hurt other guards. What's that? You can crowd them together while they chase you? You don't say...
 * It also has one that can specifically be used to get an achievement. There's an achievement for staying in combat for 10 minutes. You can get the guards near vigilantes, and the guards will just keep running into the vigilantes without knocking them down, going around, etc.
 * In the sequel, if you jump on a beam about 3 meters above the ground and your legs are pulled up, enemies can't reach you with their weapons, so they switch to throwing stones. As they do, they holster their weapons. Then you can assassinate one or two of them and jump up again and repeat. Amazingly effective.
 * In Super Robot Wars, various MAP attacks aren't fun, since they either amount to powerful Spheres Of Destruction or Wave Motion Guns. In either case, the accuracy means most of your units will get hit, and most of those will die after one or two shots. However... if the attack would hit even one other enemy unit, they won't use them.
 * Another way to work around these is to move four characters who know Alert and have the Regen 10 SP skill surround the MAP able enemy and move all other units out of the MAPs attack range, eventually, since MAPs are all ammo based, a patient player can wait for it to use up these moves and then move in.
 * In some SRWs the AI uses their MAPWs indiscriminately, most notably in A and OG2.
 * Attempting to convert a unit with two priests at once in the original Age of Empires I would leave it unable to decide which to attack, resulting in the unit standing still until converted.
 * Also in Age of Empires II, the AI was programmed to attack walls but not gates, so making your wall entirely out of gates would make it basically indestructible.
 * Another tactic to exploit this is build one of your gates directly in front of the enemies' gates, keeping them locked in their own city till your forces are ready to overwhelm them.
 * In Age of Mythology, one way to stall a Titan-level enemy was to build lots and lots of little wall pieces near their base. The AI soldiers see them and think "Enemy structure. Must destroy." and they do just that, giving you extra time to build an army or team up with other players.
 * Another Age of Mythology wall example: the A.I. can be herded into ambushes consisting of your entire army. Repeatedly. See, if you build a wall all the way around your base, the A.I. will choose what it believes to be the weakest point and attack. However, it is also programmed to seek out gaps in the wall. Therefore, the best way to secure your base is to make a wall that goes almost all the way around it, and then simply park your army in the gap. As long as they can get there, the enemy will always beeline for that one spot.
 * In the second Gothic game, it is possible to reach the besieged fortress at a level too low to fight the hordes of orcs camped around it. These can and will eviscerate the nameless hero in a handful of hits. However, there is an Invisible Wall at the start of the log leading up into the fortress which blocks enemies only, presumably to prevent the NPCs from being attacked. Neither the orcs nor other monsters realize the existence of this fence and it is possible to cluster the entire population of the map at the foot of the log for some easy Level Grinding while The Hero remains just out of sword's reach.
 * In the first-generation Pokémon games, the computer would always primarily use an attack Super effective against you. So what happens when an enemy has the move Agility available and you have a Poison-type out? Well, Psychic beats Poison, and technically Agility is a Psychic attack, so the computer would spam Agility! Agility isn't an offensive attack, so spamming it against a Poison-type Pokemon and not doing anything else will lead to inevitable failure. BRILLIANT! Oh, and the best part: The computer has infinite PP, so they will never stop using Agility! The computer's cheating habits actually backfired against it.
 * They would also use attacks Super Effective against their foe's type even if said foe had another type to cancel it out. Take, for example, Poisonpowder. Super effective against Grass, but did nothing to Poison types. And did you know that every single Pokemon in the Celadon Gym had Poisonpowder? A brand new, Level 5 Bulbasaur never took damage once because the foes would only use Poisonpowder, which Bulbasaur was immune to. And, thanks to the blatant lack of Poison moves in the first generation, that was the only Poison move any of them knew, since the only other options were Poison Sting, which none of them could learn, or Acid, which none of them had.
 * In Pokemon Stadium 2, Gym Leader Chuck is programmed to lead with the move DynamicPunch and then use the best possible move after it hits. If you use a Ghost Pokemon, which are immune to the move, Chuck will continue to use DynamicPunch, giving you 5 free turns to KO each of his Pokemon. This even works in Round 2!
 * Prior to Generation IV, computer players (unlike human players) never switch their Pokemon, even if the matchup is extremely unfavorable for them (except for Agatha and a very few other trainers, namely cooltrainers, who wastes a lot of moves switching their pokemon every other turn for no apparent reason. Gen 3 Blue will swap if his Pokemon is put to sleep and slowly dying.). If you use Trick to give them a Choice item and lock them into using a single move, then you can switch to a Pokemon that resists that move and setup to your heart's desire. Amazingly, the computer won't switch even if they're forced to Struggle.
 * Even in Gen V AI trainers still switch out so rarely that for one to do so is an event in itself.
 * Gen V has a Pokemon, Zoroark, that disguises itself to look like another Pokemon in your party, but it still has the same moveset and Dark typing. This masquerade is revealed if Zoroark is hit with an attack. Unlike with many games, this affects how the AI plays, so when fighting a trainer using Psychic-type Pokemon, a Zoroark can disguise itself as a Poison-type Pokemon, and as Psychic is super-effective against Poison but fails against Dark, this caused the AI to continuously use Psychic-type moves against my Dark-type. The Zoroark's illusion was never broken, and it became impossible to lose.
 * Dante in Devil May Cry 4 is That One Boss for a lot of players and is considered a Perfect Play AI. One of the reasons for this is if you try to shoot him, he will knock your bullet away with a bullet of his own. However, while he's shooting your bullets, he's vulnerable to attack. Get him into a shooting match and you can make him eat your Devil Bringer, even on the highest difficulty.
 * All the robots in One Must Fall have strategies that the computer always seems to fall for. Perhaps the most mind-numbing one is to just keep using the Nova's crouching sweep kick. The computer never blocks it and will just walk into it over and over again. Likewise, the computer doesn't know how to dodge the Shadow Grab. And possibly the first one that every player learns is fierce low kick right off the start of the fight, which pretty much no computer opponent will ever stop.
 * It also has serious problems with the Jaguar's overhead throw.
 * In Major League Baseball for the NES, throwing a slow pitch would make the computer batter move toward the front of the batter's box. It was possible to throw a slow curve ball to the left that did not cross the front of the plate (so the computer batter wouldn't swing) but did catch the back of it (so it would be called a strike). Using this one pitch repeatedly, it's possible to pitch a perfect game of 81 consecutive strikes.
 * The AI in Golden Axe doesn't take holes in the floor into account, which means it is easy to trick any computer opponent from walking or jumping into the game's many Bottomless Pits. Speed Runs rely on this.
 * In Iji Komato Sentinel Proxima's AI has a few bugs in it, making it possible to trap it into a non-attacking infinite loop. The creator actually pointed this out in a Youtube video of how to beat it. It may have been intentional, given that Proxima is a robot in-game.
 * The AI of a normally overpowered Komato Annihilator can be exploited to have it destroy itself with its enormous firepower in certain areas. If Iji jumps up onto a wall that the Annihilator cannot reach or break down and stays in front of the Annihilator, the AI's typical reaction would be to fire the Shocksplinter or Splintergun at Iji. This causes the weapon's explosions to rebound against the wall and back onto the Annihilator, dealing it Splash Damage. Have the AI repeat this several times trying to damage Iji, and eventually it will explode upon running out of health.
 * The arcade classic Defender had the Mutant Reverse Line. The playing field is Wrap Around, but the deadly mutant aliens never took advantage of this: Players crossing the threshold would cause any nearby attackers to scurry off in the opposite direction on the long way around. But given the game's vicious difficulty level, no one complained.
 * Another arcade classic Robotron: 2084 had the "Mikey bug." On the fifth level, there are about a dozen Mommy clones and one Mikey clone. The brain robots would all seek out Mikey and ignore the Mommy clones. If you could keep Mikey alive, and not rescue him, you could finish off most of the brains and then score a huge number of points picking up the Mommy clones. Here's an example.
 * Many levels in the GBA Advance Wars can be taken out simply by relying on the AI's loathing of resupply trucks. You can sneak a lot of units through enemy-occupied territory just by distracting the computer with them.
 * The AI also has a severe loathing of infantry in the process of capturing a building, even if the infantry in question has 2 HP and will need something like 10 turns to capture. It's always good to have some infantry to sacrifice reinforce your tanks.
 * CO Powers that auto-target a particular clump of units can be beaten with expensive bait. Take the final mission of [AW2]. Sturm would throw his meteor after the expensive clump of bombers in the lower corner instead of the cheap tanks assaulting his Wave Motion Gun at the top of the map.
 * In Advance Wars II, the AI knows that infantry are important. So much so that if it has fewer than 3 infantry, it will always build more, regardless of its wealth or needs. Getting out some AA guns and slaughtering infantry every turn makes levels trivial, as the computer won't ever build tanks to oppose you.
 * Star Wars Battlefront 2's AI is programmed to duck and roll if you throw a grenade at them. Good in theory, and works well in most cases. Just not on the Death Star. The map features railing-less walkways over bottomless pits, and I'm pretty sure you can tell where I'm going with this.
 * One of the most common AI Breaker tricks in a resource-gathering-and-management RTS is to starve the computer opponents of resources. They usually are not programmed to handle situations like that. At best, they stop trying to attack you directly and waste time throwing inadequate forces against your control points, trying to recapture a resource generator. At worst, they switch to turtling and never make another aggressive gesture.
 * Sadly, this is probably the most reliable way in all of gaming to catch an AI cheating on no uncertain terms when it continues to produce a humble army again... and again... and again... and again, when it clearly didn't get enough resources for the first wave before you completely cut it off. This happens in way too many games.
 * In Heroes of Might and Magic IV, during a siege, a defending AI would never send its melee units out to attack your troops unless you had knocked down the castle gate, making winning such sieges a trivially easy task of "shoot the shooters first".
 * In Heroes of Might and Magic II, the AI ALWAYS attacks the strongest ranged units first. While most ranged units are rather fleshy, thus making this a good tactic, if you have two titans and five hundred wizards, the wizards are massively outdamaging the titans, yet the AI will still waste their attacks on the titan's massive HP.
 * Even better - in HOMM2, archers are inexplicably ranked ahead of all other monsters in terms of priority. Meaning if you have but a single archer in your army, the opposition will go after it first - even if you have thirty black dragons or fifty titans at your disposal.
 * As evidenced by this series of 11 videos, The SA-X in Metroid Fusion isn't always the highly intelligent life-form that the galactic federation believes.
 * In Metroid Prime 3, the Screw Attack will kill Gandraya in 6 hits. Hilarious if you let her grab you, because when she disengages she is at the perfect Screw Attack distance. You can't hit Meta Ridley with this, because he will immediately stop his (time-consuming or vastly more dangerous) attack for an easily dodged Ground Pound. Saves time and health though.
 * There's a well-known example in Starcraft: if you wall off a chokepoint with buildings that don't attack (generally Terran supply depots) and then put ranged attackers behind those buildings, the AI's Zerglings or Zealots will run around in front of the buildings looking for a nonexistent path while you shoot them to ribbons.
 * There are two examples of this in Starcraft 2. First is that the AI will ALWAYS have an attack around 6 minutes. If you build up enough to defeat that early attack, you can simply macro up to take their base when their second (much smaller) attack comes.) Secondly, The AI can never respond to cheese (very early offensive tactics) which allows you to always win if you use those tactics.
 * Twisted Metal 2 is about this. Park on a rooftop where the enemies cannot get to you, avoid the occasional missile and wait while the enemies pile up down below and hit each other while fruitlessly spamming their weapons. The only level that cannot be beaten this way is (for this reason) by far the hardest. But it is fair: The AI Is a Cheating Bastard and if you attempt to fight honestly, you'll get blasted with an endless chain of freeze missiles with no hope for escape or get 20 special weapons in your face.
 * While the final boss cannot be beaten this way, he fails at another cheap trick you can exploit for all it's worth: land mines. Just drive around the city, dropping long grows of mines. Eventually he WILL roll over them, taking tiny amounts of his enormous life bar until you can finish him off in a regular shot or two (or just finish him with mines, really)
 * Why use mines when you can simply play hide and seek in one of the buildings?
 * NHL Stanley Cup for the Super Nintendo had a flaw where performing a full-power slapshot from one of the lines would cause the puck to fly over the opponent goalie's head directly into the goal, as being that far out made the goalie pull out.
 * At least in the DS port of Disgaea Hour of Darkness, there is a simple, if time-consuming method to defeat some monsters, especially low movement ones like the zombie king in the Cave of Ordeals. If you end your turn with all of your units out of reach from most melee-based enemies, they'll sit there doing nothing like in The Elder Scrolls examples above. One powerful spear technique, Avalanche, deals a lot of damage and then sends you flying backwards quite a long way. You can then set up a chain throw to clear the spearman and everyone else out of there. So long as the monster behaves like this, you can run in and Avalanche to escape as long as you like, and the monster will be none the wiser. This doesn't always work because some monsters behave differently - it's probably not going to work on a fast monster, but it's really handy when it does, allowing you to handily defeat enemies you otherwise couldn't without Level Grinding.
 * In Dissidia Final Fantasy, the AI can't dodge Shantotto's bio correctly, so it often ends up getting hit or dodging into either a stage hazard or another one of her attacks. The AI will just randomly spam dodges whenever one of her air spells is anywhere near them, unless bio is also near them at which point they don't dodge and get hit by both of them.
 * Also, when you start charging an attack outside of their reach, the AI gets really confused and doesn't know what to do, even if it's not damaging. Strange enough, they look even more confused if it's not damaging: try EX-Charge with Gabranth a few meters away and look at that enemy running in small circles and blocking every other second.
 * Duodecim takes this even further with Yuna's Mega Flare. Just watch as the pinned enemy eats a face full of purple lasers, unable to do a damned thing.
 * Feral Chaos, normally an SNK Boss. It's not uncommon for him to wipe out almost your entire party. And yet, he falls easily enough against Kuja, raining Ultima spells while gliding at the very top of the arena.
 * The campaign missions in Warcraft II can often be dealt with by throwing your starting forces into suicide runs on the computer's transports (which the computer rarely if ever rebuilds) and/or town hall, buying all the time you need. Dungeon Bypasses and the computer's inability to marshal distant forces when under attack help.
 * Jousting quests in World of Warcraft: Wrath of the Lich King can be frustrating because the AI is always faster than you and has a shorter cooldown than you on all the moves. However, after a set period of time they will always, always turn and ride away, giving you ample opportunities to hit them in the back and charge them down.
 * Also, you can spam the thrust attack to get a melee hit while charging. Best tactic is to hold on strong with thrust spamming, wait until he turns and runs, charge and thrust. While your charge takes you past him and winds down, turn around and spam the spear throw to get in that attack as well and get in close to repeat the cycle. The idea to charging first instead of throwing and then charging is that the latter often gives the AI time to charge before you, while the former denies this. Every cycle, your opponent can lose up to 2 shield charges, costing you a single one at most you can recover immediately.
 * Even easier, you can beat every AI jouster while taking nothing but thrust attacks by abusing their minimum range. Run past them and jump while mouse turning so you're going backwards while facing them, and you can use shield breaker or charge instantly as soon as the abilities light up. The AI will attempt to close to melee and will never use their ranged abilities unless you run too far.
 * In Street Fighter IV, the computer is helpless against E. Honda's command throw if you use it just as the AI is getting up after a knockdown. This conveniently leaves you standing right over them, ready for another throw. It will also repeatedly walk into Zangief's spinning lariat. Individual characters also have their own AI flaws - at a certain distance, Honda will always jump into fireballs, allowing you to spam them relentlessly; and Blanka will always attempt to block some multi-hit specials with a Focus Attack, which does not work.
 * One specific to Round Two Seth is exploiting his tendency to jump backwards and then wall-jump forwards: hang back, jump over his sonic booms a couple of times, and hit him with any sort of rising attack. Repeat as necessary.
 * In Guilty Gear Accent Core, the AI will not waggle its virtual stick to get out of stagger. With correct timing this allows you to repeat certain attacks (Ky's forward HS, for example) almost indefinitely, when a human opponent would be able to break out easily. Also, the computer will almost never block Slayer's charging punch, even after you've used it a dozen times in a row.
 * The Wii-version of Marvel Ultimate Alliance 2 has all the enemies, including the boss, home in on the character you're controlling. Considering that you can block infinitely, and that your allies will do some damage while you block, you can beat some of the bosses by taping down the block button and waiting for a while (though it does take a while to do that).
 * In several of the Fire Emblem games, the enemy AI will always target an unarmed unit, even if the attack is guaranteed to miss or deal zero damage. This can easily be used to bait enemies into wasting their powerful weapons on an unarmed general over a healer that could easily be killed in one hit.
 * Stronghold was plagued with an AI that would always send its melee troops to the nearest gap in the fortress walls instead of attacking the nearest or weakest wall. This allowed the user to set up elaborate death traps of burning pitch fields and endless rows of archers to decimate the incoming hordes as they marched mindlessly toward the 'weak spot'.
 * Or even better mazes.
 * Blade Man from Mega Man 10 is a really annoying That One Boss for those new to the game. He jumps all over the walls and ceiling, giving you little opportunity to attack him, and his signature move is a spread of three painful thrown swords aimed at the player. However, if you get familiar with his movement, and know where to stand and move such that his swords will ALWAYS miss, he becomes the most predictable boss of the eight.
 * In Mega Man 4, Toad Man's A.I. is all kinds of broken. First off, he will only use Rain Flush if he's a certain distance away from you; get right up in his face, and he'll try to jump on you. This leaves him open to a Mega Buster to the back, causing him to jump again. Lather, rinse, repeat. Even better, those of you with good timing can stand just far enough away and pelt him with Buster shots in a certain rhythm; time it correctly, and he will stop and restart his Rain Flush animation every time he takes damage, rendering himself completely immobile.
 * Elec Man can kill you in three hits with a hard to dodge attack, but timed correctly, you can prevent him from ever attacking.
 * Rather hilariously, the final boss of Mega Man X 7 can be defeated with Zero by taking about two steps forward, then two or three steps (depending on camera angle) to the right and then holding down the button that executes Zero's reflective guard move. The boss either misses or hits himself with every attack. The actual position is a little tricky to get into, unfortunately, but once there, you're set.
 * Boomer Kuwanger in the first X game after half of his health is depleted will continue to teleport around. If the player stands in the middle and shoots left and right, there's a good chance Boomer Kuwanger can't attack back.
 * Three Mega Man 2 bosses are reactive. Metal Man will not attack unless Mega Man does (or the player waits a while) and Crash Man will only jump and attack if Mega Man jumps or shoots. Heat Man however, takes the cake. It's possible to force him to do his charging attack if the player times shots correctly, and all the player has to do is jump over him.
 * Guts Man is particularly good at this in Mega Man Powered Up.
 * Rock Man 4 Minus Infinity: Using Recycle Inhaler to trap Snatchman in an E-Tank gives Rush back to you. You can use this to One-Hit Kill the boss with Rush Cannon.
 * The AI in Red Alert 2 will always (and we mean always) fire their once-per-ten-minutes superweapon at the most expensive cluster of your units and buildings possible. Usually this means your War Factory, source of your main assault forces. But the Naval units you can build rack up the expenses pretty quickly as well, and superweapons do next to nothing to Naval production facilities. Cluster a bunch of Subs/Destroyers/Aircraft Carriers/Dreadnoughts around your Naval Yard, then have them scurry off when the Superweapon alarm goes off. The Superweapon lightly grazes the naval pen, and you lose nothing.
 * The AI also targets whichever War Factory is set as your primary building (where the units come out). So you can build one away from your base and set it as the primary just before the AI fires the superweapon, drawing the fire.
 * On campaign missions, the AI also build along a fixed base layout plan. Block the predefined location with a unit/building and the AI won't rebuild what was originally there. Also, AI units appear to be permanently stuck in Guard mode, meaning that they are very susceptible to luring via shooting them with artillery then retreating behind a wall of tanks. The AI will mindlessly charge the wall and get slaughtered.
 * Invaders in Dwarf Fortress automatically take the shortest route to get into your fortress, preferentially heading for unlocked doors and avoiding locked ones, even when they have creatures with them capable of bypassing said locked doors. Because of this, it's quite possible to set up the entrance to your fortress with two doors with a long corridor full of weapon traps between them and constantly switch which of the two is locked, leaving the goblins marching back and forth through fields of + enormous steel corkscrews+ and * giant swinging iron axe blades* until blood drips from the ceiling.
 * This can be exploited even more hilariously (if more complicated to set up) by having two rows of 1x1 retracting bridges that are all linked to the same lever in a way so that you have a checkered pattern of bridges that are retracted when the lever's down and drawbridges that are extended if the lever's down. The invaders need to move diagonally every step to get through there, but even if you switch which of the bridges are retracted and which aren't, there is still always a way. If you order a dwarf to repeatedly pull the lever, the goblins will happily march over the bridges until they suddenly vanish under their feet. Using drawbridges instead of retracting ones is less safe (because big creatures can keep the bridges from operating), but even more hilarious because it flings the goblins!
 * The AI will also dodge attacks without taking into account what it's dodging into and what's it dodging away from. Construct a narrow bridge over a deep pit and cover it with crappy wooden extending/retracting spikes, and even the toughest of (non-flying) enemies will dodge right off the edge and start falling. Nothing in the game is immune to fall damage.
 * AI units do not react to enemies they haven't seen, including ones in hiding, even if they're attacked by them (though they will attempt to dodge or block those attacks). Units in hiding will also never be found out by another unit outside a 7x7 box of tiles one is in the center of. Thus, in Adventure Mode, you can stand as little as four tiles away from an enemy and remain in hiding while shooting bolts and throwing rocks at them until they die. The only time this doesn't work is dark places where you can't see enemies without getting close enough for them to spot you.
 * The effects of the Building Destroyer ability are also exploitable- a creature with Building Destroyer level 2 is not only capable of battering down doors and destroying levers and various types of buildings, it actually prefers destroying buildings to doing anything else, including attacking your soldiers unless it's defending itself. If one of your soldiers interrupts a troll in the process of battering down a door, for example, the troll will beat the soldier into unconsciousness or immobility, then leave him or her lying there and return to beating on the door. Building destroyers will also happily stand on top of traps and get stabbed repeatedly, if it gets them close to a destroyable building. Capturing many building destroyer creatures is as simple as putting a Door to Nowhere in the middle of a ring of cage traps.
 * Building on this, artifacts are indestructible. Put an artifact door, floodgate, hatch cover, or grate near your entrance, put up a marksdwarf post (with fortifications, of course), and prepare to turn any invading building destroyers and any goblins riding them into pincushions. Alternatively, put it in the caverns so you don't have to deal with forgotten beasts.
 * In Mass Effect 2, most enemies will tend to Gang Up on the Human and give very low priority to NPC squadmates, allowing the player to take cover and draw fire while his/her allies kill the enemies. In fact some enemies like the Praetorians never shoot at allies at all.
 * Perhaps justified, as Harbinger is specifically trying to kill Shepard.
 * Praetorians will shoot at allies, but only if Shepard is an Infiltrator under Tactical Cloak. You can take advantage of this by putting your squad on the other end of the battlefield and using them to bait the Praetorian into turning around and giving you some free shots at it.
 * Tactical Cloak is probably the easiest AI Breaker of all, since at maximum ranks (easily achievable by the end of your first one or two post-prologue missions) you get up to six seconds of invisibility (more than enough time to relocate behind the enemy), an extra second or so while shooting (and +75% damage while shooting from under cloak...), and you have a pretty short recharge (enough time to sit behind cover and wait while the enemy whales away at the box you're hiding behind). The AI can't find you while you're under cloak, which translates to Shepard running around the battlefield invisibly, dropping cloak every few seconds to blast the back of someone's head open with a sniper rifle.
 * In Zelda II the Adventure of Link, the end boss is among the hardest bosses in the NES era... unless you stand on the far left, duck, and just sit there stabbing over and over. The boss AI will repeatedly walk right into your sword, leading to an easy victory. Due to the difficulty of the fight otherwise, very few people even try to do it "right".
 * In The Legend of Zelda Ocarina of Time, the Water Temple boss Morpha can be easily beaten by simply standing in a corner between the wall spikes, and waiting for it to reach out to attack you. Turns out it just barely misses, with enough room to shoot your Longshot at the nucleus inside it, trap it in the corner, and hack away until the boss is dead.
 * In the Microprose Magic: The Gathering game, the AI isn't very smart in itself, but it at least seems to understand the game, until you use Black Vise and then the computer will do whatever it takes to reduce its own hand, even if the move itself is worse than just taking the damage or even if there's an obvious, obviously better move (using a card to kill his own creatures when he can kill yours, for example), and even if it's well below the four-card safe range.
 * In the Naruto Ultimate Ninja Heroes games for PSP, the recommended tactic is to use the backwards doubletap, tricking the AI to rush forward to catch up to you, during which is he vulnerable to a forward doubletap rush leading into a combo he will be unable to counter out of. Rinse and repeat through the insane difficulty story mode.
 * Pac-Man is completely deterministic - if you make the same moves on a given level, the ghosts will always respond the same way - allowing players to develop and memorize patterns guaranteed to clear a level if executed correctly. Here's the particularly show-off-y "Donut Dazzler" pattern. Ms. Pac Man simply randomized the ghosts for the first 7 seconds to avoid this.
 * The first Command and Conquer was full of these.
 * Attacking an enemy harvester would always make the AI empty its base to defend the harvester with everything it had.
 * Building a wall of sandbags or other barriers allowed the player to completely trap the AI in its base. It never intentionally tries to destroy them.
 * The AI would rebuild its bases according to the predetermined layouts if any of it was destroyed, and it would ALWAYS replace lost buildings if it had the financial capability to do so, allowing the player to drain their funds easily if a vulnerable building could be found to continuously whale on (and the AI would always spend money to repair damaged buildings). The final mission of the GDI campaign actually seems to be designed to allow the player to exploit this; a large group of Nod tiberium silos is concentrated outside of the main base, allowing the player to continuously capture them (stealing the money inside), sell the silos and transfer the stored tiberium to their own storage facilities, and then the AI would then rebuild them and fill them up to be captured again. On the flip side, another GDI final mission has the AI suddenly start building near a tiberium field, making the AI rather dangerous.
 * The AI scanned for targets starting from the top left of the screen, possibly assuming that was where your construction yard was. This meant that you could defend against airstrikes by putting a minigunner northwest of your base. This was much more cost-effective than building multiple SAM sites to destroy the planes, which had no rebuild cost. It also meant that you could potentially stop your base from ever being attacked, simply by diverting the AI away from it.
 * Similarly, with Engineers the AI always tried to take over your Tiberium silos. Even if it has to walk past your Construction Yard or other valueable buildings, not to mention other units eager to shoot them, to get there. When you don't have silos, it may send Engineers into defense structures, which can't be taken over. (You as the player cannot give such an order; when the computer does it, the engineers just disappear into the building which remains unaffected.)
 * In the novel Epic by Conor Kostick, about a world-spanning government based on an MMORPG, this is a plot point, when the main character figures out that an extremely lethal dragon can be defeated by multiple people attacking it one at a time. The dragon goes after whoever deals the most damage, so by getting a group of people together to shoot the dragon one at a time with arrows, they manage to kill the dragon, an almost unheard-of feat.
 * In King's Quest Mask of Eternity, if you shoot at the skeleton archers from a very large distance, they will never shoot back. It's not just that you're outside their range of fire--it will never occur to them to move closer so that they can shoot you. In the Underground Realm of the Gnomes, you can shoot the immobile rock demons from around a corner if you're very careful. If you stand just right, the stones they throw at you will crash against the wall.
 * The last boss for Knuckles in Sonic And Knuckles, Super Metal Sonic, has a lot of fast, hard to dodge attacks, often where hes invincible during them and can whizz around the screen. He also has an extremely slow, easy to dodge attack that leaves him completely vulnerable. And he'll keep using that one instead of his annoying attacks if you stand still in the right place.
 * In Defense Grid, on some maps, towers can be used to force the flow of enemies along a particular path. You still must provide a path for them to get through, otherwise they just run through your towers. However, if you constantly change the path, by purchasing and destroying towers, you can keep the flow of enemies in a single area, thus giving your towers plenty of time to kill them off. It does make some of the most interesting and rewarding maps dull and boring, however.
 * In the SNES version of Prince of Persia, a character backed against a wall no longer has room to recoil from being hit and becomes helpless against non-stop sword strikes. This is exploited very heavily in both regular and tool-assisted speedruns. The six-arm boss avoids this by jumping to another spot on the screen each time it is hit.
 * Arino in Game Center CX also discovered the same thing by accident when he was playing the game, which made the challenge noticeably easier.
 * In Call of Duty: Black Ops, if you blow up one of the jeeps on the Firing Range map, get in the back and crouch down, AI opponents can no longer see you, while you're perfectly free to riddle them with bullets.
 * In the NES Licensed Game version of Robin Hood: Prince of Thieves, the sword fight scenes became laughably easy when you realized that you could stand next to a table and your opponent would swing over your head while repeatedly walking directly into your blade.
 * U.N. Squadron / Area 88's stage 3 boss (the forest fortress) and stage 8 boss (the battleship) have turrets that fire at you...but only at preset angles. If you position yourself far away enough from and slightly above the altitude of a turret, you'll be perfectly safe from it while in place to pound it into pieces. The same applies to their counterparts in the SNES port.
 * In some of the Yu-Gi-Oh games (those based on the anime rather than an accurate representation of the card game, such as Dark Duel Stories and Reshef of Darkness), an opponent will always, always attack a monster you set face down. Even if you have a trap down to catch their attack. Even if your monster has an instant-death type advantage over the opponent's monster. In most cases, they'll even flip their own cards face up in order to do so, regardless of if they are decent attackers or not.
 * AI Wrestlers in WWF No Mercy can be consistently baited into running at you, if you repeatedly sprint back and forth yourself. As wrestlers cannot counter most moves while running, this allows the player to bypass the impossibly frequent counters the CPU will otherwise pull off on higher difficulties.
 * In Might and Magic VII, the Champions of the Sword could be easy if you had the Dispell Magic spell. Their AI called for them to buff themselves with Hour of Power, and if you dispelled it, they'd just keep on recasting it and never attack.
 * Empire Earth has one where AI units attack whoever attacked them with all priority, even if that means getting past the wall of other units in their way. In the Greek campaign it is possible to win Alexander's battles by having a single archer move up, fire once at an enemy, and run like hell. The entire enemy army will follow and get shredded by the rest of your units, inflicting no casualties on your side (unless you let your archer get killed, then they attack anything in range).
 * In Burnout Paradise, driving the Hunter Toy Citizen in a Marked Man event makes it incredibly easy to win as the pursuing Civilians just drive right past you.
 * In Dungeon Keeper, the Computer's Keepers would drop their entire army on an intruder that is seen on their territory, while you can only pick up 8 creatures at a time. You can turn this against them later in the game when you get the spell Destroy Wall. All you have to do is find the enemy portal (which you already see at the start), and destroy some of the walls around it, leaving bare earth. Drop an imp on it, and you can see into the enemy base (at which point you can cast lightning, picking off the enemies one by one). The AI breaker comes when the enemy spots the imp next to the portal, and drops its army on the portal because it is next to the imp, at which point you pick up the imp. A good number of them will walk into the portal, as dropping a creature on the portal dismisses it. Repeat this a few times, and the Keeper will have removed most of its strongest creatures without spilling a drop of blood. It's best to do this on a level where gems are available, as this can be costly.
 * The AI of Sword of the Stars doesn't really know how to deal with mines beyond "hope our PD can take it."
 * It also can't handle deflectors or disruptors, forward-only shields that are completely impervious to projectiles or energy weapons. Just make sure the appropriately equipped ship is in the front and the enemy will happily waste time shooting at the shield instead of trying to get around it. This is particularly effective against the Liir and Morrigi AI, which have a strong preference to only using energy weapons.
 * In Touhou 9: Phantasmagoria of Flower View, the lasers in Shikieiki's boss summon Spell Card (level 4 Charged Attack) are an AI breaker, because the AI only plans ahead a couple frames at a time. Like most other Touhou lasers, it gives plenty of warning with a thin line marking the path where it's about to fire, which any human player would see as a sign that they should get out of the way ASAP. The AI will ignore the warning and dilly-dally, try to move out of the way at the last second, and get hit because the laser is too wide for them to move far away enough before it hits.
 * Most of Aya's attacks, in normal gameplay, can be easily avoided by simple bullet streaming. The AI, however, doesn't bother with such tactics, and promptly takes a shot to the face due to its poor handling of fast-moving bullets. This can reduce the amount of time the AI survives by nearly 50%.
 * In Killer Instinct, you can easily beat Fulgore by dashing in, stopping right before you're in range, and jumping back. Repeat this for long enough, and Fulgore will try and uppercut you, leaving him open for an attack. You can do this for the entire match and he won't stop.
 * Persona 3 has a very difficult boss called World Balance, so tough that its entry under That One Boss theorizes it has an adaptive AI. However, if you put up a Magic Mirror, World Balance throws a tantrum and starts spamming Megidoloans at you. While this may seem like a bad thing, by this point in the game you should be high enough level that your party can just barely survive the damage from a Megidoloan. So, all you do is set your party to "Full Assault" tactics, counter-spam Mediarahan (Full party heal) with the main character, and wear him down steadily.
 * In Knights of the Old Republic II, the last section of Telos has an optional battle against the Handmaiden sisters. First you fight one, then two, and then all five. Whoever falls or is forced off the mat first wins. All five will attack you at once and beat you to death instantly. While it is theoretically possible to win fairly, it requires a very specific build. Instead, the easiest way to win is to charge a melee shield, end combat, and place your character right in front of each Handmaiden individually. By doing this, the game has to move the NPC backwards to the minimum attack distance. Repeat until all five are forced off the mat. You win without throwing a punch.
 * There's a Bonus Boss in Chrono Cross who is, if you fight him normally, incredibly hard. He has a bunch of extremely powerful Black-element attacks, and any time you try to use a spell or skill against him, he immediately counters with an opposite-element reaction. The problem? Countering uses his turn. He becomes pathetically easy once you realize that all you have to do is have one person equip the armor that absorbs Black and spam White spells, and the other two spam Red: he'll keep blasting the first one with a devastating Black-element attack which now heals them, and hitting the other two with a debuff that reduces their evasion rate but doesn't actually cause any damage. This is particularly handy because it lets you get Serge's Infinity-1 Sword way before you're supposed to.
 * Using Spider-Man's slide kick attack at just the right distance makes fighting Puma in the Game Boy Advance version of Spider-Man 2 a breeze, since he just stands in place as you hit him over and over again.
 * Up until NHL 2001, the goalie AI was so slow at poke checking, skating in front of the goalie would cause it to attempt a poke check with the player free to shoot on an empty net.
 * Ghostbusters the Video Game has a particularly frustrating scene where you must use your capture stream to throw possessed stone angel statues into a magical gate. This is a very difficult task as the angels are fast and have a powerful attack, while the capture stream slam is very hard to aim well. But, if you stand right in front of the gate and strafe left and right, the angels will crash into it while trying to charge you and complete it for you.
 * MM Os in general, just by their very nature of (nearly) anything being possible, often have issues with this - as they have to make the AI fluid enough to allow players to use different strategies, while smart enough to prevent exploits. Since players tend to come up with solutions that the developers haven't thought of - this leads to more exploits than in other games.
 * In one of the early Elf quests of the Epic Story line, in The Lord of the Rings Online, you're charged with rescuing an elf, where you have to carefully navigate through a fortress city, avoiding patrols (which will spawn more mobs) until you reach the ship the elf is held captive on. However, this part can be easily breezed past by simply making a bee-line to the ship, jumping the side rail, and standing behind it. All the mobs that aggroed and spawned will be stuck on the railing, failing to path to the part with no railing, and instead, trying to rush directly at you. At this point, you can just pick each of them off at your leisure with any ranged skill you have - before advancing the quest by talking to the elf.
 * The Final Boss of The Twisted Tales of Spike Mc Fang can be manipulated into getting stuck at the side of the throne on the top of the arena while the player stands on the other side of the throne throwing boomerang hats and easily dodging his very powerful attacks.
 * Melee combat in Rondo of Swords is based around the Foe-Tossing Charge, so enemy melee units typically don't move until you're close enough that they can charge you. However, they can't end their turn in an occupied square, and they can't double back on their own path. If you put a unit just close enough that they should be able to charge it, then put three more units in the three adjacent squares they'd charge past your nearest unit to reach, they'll get confused and move to the one open square adjacent to your nearest unit--which not only prevents them from damaging that unit, but allows your four nearby units to gang up on them on the following turn. (Note that this does not apply if the enemy unit has a significantly shorter movement range than your nearest unit--they'll try to flee instead.)
 * Minecraft, for a long time, had enemy AI be very simplistic. If a monster was chasing you, all you had to do was stand in front of a pool of lava and watch the mobs walk straight into it. The AI was coded to walk in a straight path to the player when they spotted them, regardless if there was a lava pit or a cliff in the way. The update to 1.2 enhances the AI to have better path finding so if the player is being chased by a zombie for example, the zombie will attempt to look for alternative paths to the player as long as it doesn't hurt itself. Skeletons were also made smarter by rushing at the player and flanking them should the player hide by a corner of a wall. Enemy mobs can also see through glass and will try to get to the player if they see them through the glass, whereas in the past, glass acted like solid blocks for mobs, thus they couldn't see through it.
 * Endermen also have an exploit in their AI that can be abused if used right. Endermen take damage from water and if an Endermen is hostile towards you, exposing it to water will cause it to be neutral and stop attacking you.
 * Terraria has a similar pathfinding problem. Enemies only know how to reach you in a straight line, meaning a simple thin lava pit on either side of a house means infinite money as the enemies stroll in and immolate themselves. On the flip side, this will usually destroy loot in the underground areas where the lava is too deep. Enemies are also too stupid to walk around an obstacle when you're above them, since they only target you by the y-axis. This allows to effectively lock some enemies on a higher level of blocks (which you can often build on the fly if hotkeyed) while attacking others.
 * Final Fantasy Tactics has a few of these, but they're rare or situational enough that it's generally easier to either get better at the game, or level grind. However, players engaging in challenge runs need every advantage they can get, and there are a number of well known tricks for various bosses. The most notable of all, however, is known as the Loss Strategy. Loss in an ability possessed by numerous bosses (in particular, the hardest ones) that can inflict the confusion status with 100% success rate. A confused unit will run around the battle field using random abilities at random targets. The AI is hard-wired to never break confusion unless it knows it can kill the target in two hits. Normally, this is not a problem, but in a solo challenge, when the player is confused and the boss cannot kill him quickly, the boss either does nothing, or uses mostly harmless spells that can't actually kill the player. With no allies to attack the confused character can only attack the boss. This means that many otherwise strategy intensive boss fights end up reduced to 'get confused with enough HP, enjoy a drink while the random AI slowly kills the boss'.
 * Left 4 Dead and its sequel has some parts of the map where the zombies somehow become blind to your presence, even if they are within arms reach of you. Due to bugs or just faulty AI navigation, being in certain places causes the zombies to act like they cannot reach you anymore. Similarly, Tanks can suffer the same problem and they will die after some time since it's programed to suicide if it cannot see or reach the survivors after some time has passed.