"Explosions tear up both your cover and the enemy's and you don't have the super homing x-ray vision bestowed by the NPC gods."
Despite what publishers would like to tell you, there really is no such thing as Artificial Intelligence
in video games. Most video game AI systems are, ultimately, nothing more than complex flowcharts. Because of this, it's very tricky to make computer opponents behave the way a human player would. While it's possible to design an AI that receives data similar to what a player receives, then analyzes it to make a decision, this is immensely
difficult. Since the AI is an integral part of the game engine, a far easier (and thus much more common) technique is to simply pluck the information directly from the engine, and base all AI decisions on that.
The consequence is that computer players can get an unfair advantage over humans: It isn't bothered by dark colors or (loss of
) environmental lighting. Its performance isn't encumbered by Interface Screw
, Damn You, Muscle Memory
, or any amount of nested menu navigation. And since it's part of the same engine that keeps track of where your players and units are on the map, if the AI wants to mount an attack, it knows where to find you better than you do
, Fog of War
(or even walls) be damned.
The AI is the narrator of the story; if you win, it's only because it told you so.
Of course, this doesn't always make for a fun playing experience
. To bring back the fun, programmers must make the AI act
like it has the same limitations as a human; anything it's not supposed to know for the sake of game balance, it has to tell itself not to know it.
When it doesn't, you have an All Seeing AI: Stealth is useless, no surprises are possible, and it will (almost) never miss a shot. Consequently, single players should not bother with misdirection, flanking, or other forms of deception and psychological warfare that would work wonderfully against actual humans. This is often the reason for Useless Useful Stealth
in games that are not specifically stealth-centric. In a similar manner, high-difficulty-setting fighting game opponents can react with inhuman speed and precision to counter your move before you can even use it properly.
A part of how The Computer Is a Cheating Bastard
, although it isn't strictly
cheating, as the AI doesn't bend the game mechanics as such.
- Advance Wars AI is often unaffected by Fog of War: they still can't target enemies hidden in forest/reefsnote and don't factor in the health of enemy units out of their supposed vision (making it effectively the same as not knowing it), but still know where every unit is.
- This was finally fixed in Dual Strike and Days of Ruin.
- Driver and Grand Theft Auto frequently feature opponents who always know where you are, no matter how fast you run or how many times you change cars.
- In "Grand Theft Auto V" , the police will still triangulate a player that has killed a NPC or another layer, despite using a silenced weapon, avoiding public view, the distance the shot was fired from, and hiding behind solid walls. Police appear to know where and who to arrest within a second of committing a crime.
- In the President's Run, the cops know your position from the very start.
- In Super Smash Bros. Melee and Brawl, no Interface Screw in the world is going to deter the AI. Examples include:
- In both games, the AI notices when items have appeared off screen, which can result in it running off in the middle of a heated duel to grab an item that it shouldn't have even noticed until it came on screen. This only applies to overly large stages though, as the majority of stages are small enough to stay entirely on camera the majority of the time.
- When Togepi appears in either game and performs Night Shade, the screen goes completely black. You can't see what the hell you are doing, but the AI knows exactly where you are in the darkness, making this Pokemon move more of a hindrance.
- In Melee with the Cloaking Device item, which turns the character invisible, but does nothing to deter the AI.
- In Melee 1P mode, instead of being used to input smash attacks, the c-stick instead adjusts the camera. This is entirely useless though, as all it does it screw with the interface and obstruct your vision, while you're fighting cpu opponents who always know where you are regardless.
- When the Nintendog appears in Brawl, nothing happens to the AIs.
- In Brawl, the AI have perfect bearings when the controls or the stage in Spear Pillar is reversed, making the fight much harder than it needs to be.
- The Command & Conquer: Red Alert series feature Gap Generators, structures which create a permanent shroud above itself, effectively hiding anything that is covered by its radius of effect. It is somewhat effective in multiplayer for long games, because it can hide units and structures, forcing your opponents to guess what sort of attack to send your way. However, it's completely useless against AI opponents, which are omniscient and can target any specific unit or structure, even ones that it isn't supposed to see. To be fair, the AI still won't be able to send any standard aircraft to attack units/structures within the Gap Generator's field of effect. Special Weapons utilising aircraft (Paratroopers, Spy Plane, Parabombs), however, can and will be used by the AI when possible.
- The whole "Stealth is useless in single player" theme is continued in Zero Hour and Tiberium Wars. Nothing, up to and including cloaking your entire base and any units, will stop the enemy from finding them. Sure your army may be stealthed, but without even any stealth detection units (normally required to be able to fire upon stealth), the AI will blow your men to pieces in skirmish mode.
- Tiberian Sun also cheats in skirmish mode. No matter the difficulty, the AI knows exactly where your Construction Yard is, even if you moved it halfway across the map prior to deploying it, so long as they have seen any of your units. Even a lowly Scout Bike.
- More annoying than this is the ability for the AI to send subterranean AP Cs full of engineers or other troops right into the middle of your base, even if the AI has never seen your base . When you have control over the same AP Cs, you can't send them anywhere that you haven't already been. A common tactic for Nod AI players in skirmish games is to rush the subterranean AP Cs and send one straight into your base immediately, capture your construction yard, and sell it. If you didn't manage to build a war factory before this happened, then you'll have no way of getting a new construction yard, essentially giving the AI the win.
- The final DC mission of Tiberium Wars' Nod campaign is particularly notorious. If you cause a ruckus in the GDI base with Shadows, it doesn't matter in which direction you flee in. The AI will always follow the Shadows even though it clearly can't see them. If the Shadows are on the ground, the following AP Cs just run them down but if they are in the air, the followers just keep circling below until a Pitbull arrives and the shooting begins (since the units now can clearly see what they've been following blindly).
- Oddly sometimes units will follow stealth units around..and then stand next to them, not attacking but frustrating your efforts to use those units.
- Support powers from later games are a particularly egregious case. The Soviet Magnetic Satellite from Red Alert 3, for example, causes a warning flare to appear in an area, after which a beam sucking enemy units into space will fire down. Good luck seeing the flare when you're currently looking at the other end of the map. If you're unlucky, the only clue you'll have that the AI used the attack is that your fleet of Shogun Battleships has suddenly disappeared. The skirmish AI, however, will always notice, and move its units away. End result: an attack that's nigh-useless against the AI, but devastating against an unlucky human. For bonus points: you cannot use support powers in areas shrouded in Fog of War (While for the AI, there is no such thing as Fog of War), and the AI is more than happy to use such powers against hidden units.
- Not only this, since the AI can see the whole map and knows what you're building at all times, it will always build units to counter yours, and use its all-seeing power to constantly harass unguarded sections of your base, running away and attacking from a different direction as soon as you move towards it. It's basically been designed to be as annoying as possible.
- In Far Cry 2, once one bad guy has spotted the player, every goon in the area instantly knows exactly where he is and can fire with pinpoint accuracy even when the player is crouched in head-high grass he himself is unable to see through. Darkness also seems little hindrance.
- Witness in horror as your undetected assault of pirate outposts in Far Cry 3 is ruined multiple times by a drunk molotov guy or a dog somehow being able to spot you from half a mile out despite the fact that you're using bows and silenced sniper rifles, hiding in the trees, and likely hopped up on drugs that literally make you undetectable. It gets worse when you get to the second island, because the game will spawn in literal truckloads of mooks that casually drive up to your position if you take too long.
- Another silly example courtesy of Far Cry 3 - at one point on the second island, you're disguised as a mercenary and tasked with assassinating 3 merc captains inside a base. If you kill a guard and someone discovers the body, everyone instantly knows you did it and comes gunning for you, even if you killed him silently with no witnesses and are on the other side of the camp when the body is found.
- Notable in Hitman 2, which being a Stealth-Based Game is generally pretty good in this respect, is the snow pass level: the developers apparently forgot that a blizzard, at night ought to have some effect on the ninjas' ability to spot you; they're also preset to realize that your papers are fake and open fire after a five-second animation - even if you walk away and are well out of sight by the time they're done reading them. It gets worse with the snipers in watchtowers. Even if you are wearing a ninja uniform that completely covers your face, from hundreds of feet away they will instantly recognize you as an impostor and shoot you on sight.
- In Warhammer 40,000: Dawn of War, the Imperial Guard AIs not only have the uncanny ability to know exactly where your stealthed units are, but also the ability to place long range auspex (radar) scans right on top of them. To make matters worse, this ability has an unfairly short cooldown (for its effects, at least), and the Imperial Guard can have five HQ buildings and thus five scans, each on a separate cooldown from the others. This can be exploited by having some dummy stealthers around to attract auspex scans whilst the real stealth units do their work, but that's a waste for the most part. (It's a little less wasteful with the Tau or Space Marines, who have access to cheap stealth units.)
- In the Do W sequels, Dark Crusade and Soulstorm, many battles will take places on large maps with multiple possible locations for a base. Part of the game is figuring out where the enemy's base is located. The AI always knows where your base is, however, and will send units to harass you from the very beginning.
- Similar to the above, in StarCraft the Terran AI always places their Comsat Scans at the exact location of your invisible units. To be fair though, it doesn't exploit its knowledge until you give it a reason to "notice" the unit, so it's not that unfair. In a subversion, also involving stealth units, the AI is actually doing less than a human could: Stealthed units are visible to players themselves, as they blur the area they move through. Many Observers, Ghosts and Wraiths got revealed by a scan of an observant player. In Starcraft 2 burrowed Roaches and Infestors can also be seen when moving underground. Stationary stealthed units are harder to spot, and burrowed ones are truly invisible unless in the presence of a detector.
- In Warcraft 3 it is impossible to hide from the AI unless you use the World Editor to make all of your units and buildings invisible. The AI knows where you are at all times, when you're away from your base, when you start making a new base and when you are at your weakest.
- The AI in Warcraft and Warcraft 2 both fall into this trope as well. In fact, both games feature Invisibility spells that are 100% useless when playing against a computer opponent.
- XCOM: Enemy Unknown: As soon as an alien sees one of your soldiers, their Ethereals and/or high-ranking Sectoids can make psionic attacks on any of your soldiers (although they will always target the weakest non-mindcontrolled soldier first). Also, after round 20 the enemy will know your positions automatically.
- Though the second case is understandable as an Anti-Frustration Feature, if the last alien wasn't found after 20 turns it might be very boring to track him down, so if he knows where you are and comes for you it gets much better. The problem comes when you're going at an alien base or very large UFO that'll probably take more than 20 turns to clear...
- Inverted in Mario Kart Wii, with the view-obscuring Blooper Ink interface screw. For regular players, it makes it hard to see what's up ahead of you, but certainly not hard to see where the track is. For computer-controlled players, however, expect to see extreme amounts of off-course racing when it happens!
- Likewise in Mario Kart DS.
- Further inverted in DS once you realize that you could just switch to the bottom screen for the short time that the Ink is effecting you.
- Also in Sonic & SEGA All-Stars Racing(With Banjo-Kazooie), the Pocket Rainbow, which works like the Banana Peel of Mario Kart, but instead, acts like a Gooper Blooper. This is also inverted by the Shooting Star, which makes the player's screen upside-down.
- Also averted in Left 4 Dead. When AI-controlled Survivors are vomited on by the Boomer, they will stand in place and flail helplessly at the air with their melee attack for several seconds. Ironically, they are worse than human players in this instance.
- And many others.
- Although in both games in Versus Mode an AI controlled survivor will be able to spot any infected looming in the dark behind trees or crops and pick them off much to the Infected player's frustration.
- Dwarf Fortress, goblin invaders automatically know the shortest way into your fortress. The game is a good illustration of how omniscient pathing can be CPU-expensive — especially with reproducing creatures, which is known as "catsplosion". And how it can be exploited: Dorf Fortress players being what they are, they figured out that if you keep two ways into your fortress and alternately open and shut the doors hostiles approach, it's possible to get the gobbos marching back and forth through your hallways full of giant swinging axe blades and walls of rotating saws until the entire siege is reduced to a fine paste. And that with one Pressure Plate per exit you can automate it and they will never catch on.
- Also, the dwarfs always know the shortest route, even if they've never been where you tell them to go. They can't see an ambushing enemy that hasn't been spotted, but once it's spotted every dwarf will know where it is from then on.
- Interestingly, with civilizations sending diplomats it also partially compensates for the exploitable part. Goblin soldiers will gladly blunder into your traps time and time again. Piss off the humans, though, and their soldiers will remember and avoid every trap any their peaceful representative has ever seen.
- In the Rainbow Six series, once you make a noise with an unsilenced weapon or a stray bullet ricocheting, the tangos in the area will all know your position, although they can't see you yet. And when they do see you, even if you peek around a corner, they will almost always get an instant One-Hit Kill.
- If you kill a baby or eat an egg in Spore, the entire species will know. Always.
- An example that can be turned to the player's advantage; if you give any party members a "Foe: <Element>-weak" gambit in Final Fantasy XII, your allies will always know when the enemy is weak to that element, even if the enemy has immunity from the Libra effect (that reveals weaknesses).
- Inverted in Final Fantasy Tactics A2: the player can see enemies' reaction abilities, but the AI can't. This leads to the AI wasting turns by doing things like using normal attacks on units whose reaction ability makes them always dodge normal attacks.
- In Transcendence, if the player is hit by a Blinder cannon while their ship's shields are down, their visual will turn static, signifying that it is damaged. If the AI gets hit, it does absolutely nothing.
- City of Villains has two types of enemy ambushes: the first kind that simply run to the spot on the map where you were when you triggered it and will either run into you along the way or be waiting for you if you come back, and then the kind that make Stalkers scream bloody murder because they home in one you no matter where you go and see right through stealth even if they normally cannot.
- The second type was also a nightmare for Masterminds before the introduction of Bodyguard - the hostile mobs would zero in on the vulnerable player and ignore the expendable pets.
- Anyone who's played a Sram in Dofus knows that this applies. Enemies can see everything you do, and can even track (and sometimes attack) you when you're invisible.
- This is subverted now. Instead of knowing where you or your traps are, the A.I. makes an educated guess on where you are when invisible. Turning invisible, and then using 1 movement point, it will know you are on one of the squares right next to your former location, and have to make a guess based on that, just like any human player would. The same applies to Traps, as they too are invisible, only here they generally fail at guessing, and always assume you placed the trap in a perfectly linear path in the direction you are facing (Which you don't nessesarily have to). Oddly enough, even in high-tier PvP, the players are generally less intelligent than the A.I.'s anyway, as most Self-proclaimed "Pros" Generally assume everyone are predictable idiots.
- In Battle for Wesnoth, subjecting the AI to Fog of War is not yet implemented. This is probably why the single-player campaigns don't use Fog of War most of the time.
- A lot of the Yu-Gi-Oh! games before the DS's release have done this. While this was perfectly justified for Pegasus, who actually had this ability in the series, it doesn't excuse the other opponents. Of course, the reason for this before the DS could have been programming restraints.
- Ironically, Pegasus easily has the worst AI in the first GBA game, more than making up for his cheating by wasting cards, replacing his cards in play with inferior cards, and pretty much anything he can possibly do to give himself a disadvantage.
- Pegasus is always extra blatant about this in any game he's in. This is most obvious in Duelist of the Roses. In this game terrain bonuses and penalties come into effect. Most of the AIs will walk into losing battles if you play your card face down on occasion, and can be bluffed some of the time. Pegasus will accurately calculate the attack of your facedown card after all effects, and make sound decisions based on it.
- In particular, this made the card Magical Hats utterly useless; the AI would always attack the monster you were trying to protect!
- The Supreme Commander AI doesn't need radars or radar-equipped units to spot a cloaked ACU and blow it to hell with two tactical missiles (which aren't even homing, yet the AI always hits dead-on).
- The Elder Scrolls games are notorious for this. Along with the all-seeing enemies that home in on you as soon as you're within 500 yards of them (Daggerfall even let enemies see you through entire floors and closed doors), there's the all-knowing guards. Any time you kill someone even in the same general area of a guard, regardless of whether or not they see or hear you, you get a bounty on your head. Even if you're completely invisible, they'll still know you did it. Fortunately, their pathfinding in their attempts to arrest you doesn't benefit from this clairvoyance in Oblivion.
- It's not quite as bad in Oblivion; enemies actually have to see you, and there has to be a witness to the murder for you to get a bounty.
- ...Except for a special condition for both of those. Enemies know exactly where you are even if you 1-shotted their friend with a Stealth shot from a bow (even if they were looking away from you and their friend AND there's no way they could see your hiding spot), and killing a guard gets you an automatic bounty even without a witness.
- Skyrim is extremely bad about this. Often, even when the enemy you just killed is a totally blind Falmer, whom you killed with a stealth attack, with a bow, from 500 yards away, instantly, his friends (who are also totally blind) will all begin running STRAIGHT towards you with laser-perfect accuracy. All at once. It can get pretty ridiculous sometimes.
- Another striking example are the "Hired Thug" groups that are sent after you in retribution for stealing stuff. They slowly and magnetically home in on you, no matter where in the game world you are. Even if you manage to fool them for a moment, they will only roam around disoriented for a couple of seconds - afterwards, all of them will turn your way again. And slowly start creeping towards your new position. Invisibility potions, shadow, heavy fog, perfect stealth, cliffs and 10foot-thick rock cover be damned.
- Guards will also home in on you with perfect accuracy (regardless of your concealment) to complain about your Shouting. Even if you just used Aura Whisper (which, as the name suggests, is a barely heard whispering) to spot the guards in the Dwemer Museum. Who will, after telling you to stop, promptly attack you for trespassing.
- Merchants and guards in Morrowind have another kind of clairvoyance: every item has its owner's name baked inside, so when you steal something (and so ownership doesn't change), even if no one sees you and no alarms are raised ALL guards all over the world will know that it's stolen and should you be fined for sleeping in someone's bed without permission they will also confiscate the previously stolen item. Similarly, a merchant will recognize an item if you try to sell them back what you stole from them, even if it is a single arrow in a 300 arrow stock.
- It's even worse than that. If you steal say a loaf of bread from one merchant and discard it, then find another loaf of bread in a dungeon and return to the merchant you originally stole from they will accuse you of trying to sell them THEIR loaf of bread. For the rest of the game this will remain the case with that merchant and that item. For this reason in Morrowind when playing as a thief it's a good idea to not steal from every merchant you meet.
- Halo 2 has unlockable skulls that make the game harder. One of them allows enemies to see you through walls, making them impossible to catch off guard.
- The Whuppapotamus skull allows enemies to see you when you have the Invisibility Cloak on, among other AI upgrades.
- On Legendary difficulty in any game, once alerted to your presence, the AI will be able to send pinpoint fire to your location every time you poke your nose out. They can actually be facing away from the player, but the second the Chief/The Rookie/Noble Six exposes themselves, they are instantly alerted.
- In just about every shooter, there will often be a lot of dust and smoke and explosions and whatnot cluttering up your vision, but the enemy AI will almost always be able to clearly see and shoot you through it unless it's specifically caused by a smoke grenade or a flashbang.
- And in Soldier of Fortune II and the later Call of Duty games, they can see you through smokescreens too!
- In most shooters, darkness doesn't inhibit the AI's vision either.
- In the Call of Duty series, stealth missions suffer from this. In Modern Warfare, the enemies will instantly where you are if you are revealed, even by guy you killed immediately after while he was alone. For a particuarly egregious example of this trope, see Roach's first mission in Modern Warfare 2.
- Go ahead and use Reptile's invisibility on any difficulty setting for Mortal Kombat II, and see if the AI is at all inhibited by it.
- In Starcraft, the same is true. The AI is aware of everything on the map, even if it can't actually target it (cloaked units, units or buildings out of sight, etc). Even then though, they can still sometimes target them. In Brood War, for example, if you're up against a Protoss AI and they have Dark Archons or High Templar, don't be surprised if one of them suddenly wanders out of their base... they have a specific target in mind and they're going for it, or die trying.
- Also, playing against a human in StarCraft, you can hide tech buildings in a random corner of the map where no sane player would look until he/she noticed the buildings not in your base (Which in of itself, is easily preventable); on the other hand, there's no point in hiding tech buildings from the computer. You're better off putting your entire tech tree in the back of your main base, behind your army and possible stationary defenses; ironically enough, a tactic that doesn't work against humans. (Humans just simply fly over your army and defenses and go straight for important buildings, the computer attacks the first thing it comes across.)
- Like the Warcraft example above, the computer will always go for your least defended base without seeming to even know where it is before the attack.
- Blizzard really made an effort to prevent this in Starcraft II. On difficulties other than Insane, the AI does not see the entire map. But it does like to send scouts to every nook and cranny, and adapts to the units and buildings it sees.
- Bots in Counter-Strike are schizophrenic in this. If you throw a smoke grenade they run right past you if you stand in the smoke, other times on a labyrinth-like map with 3-4 paths leading to where the bot is standing, he will place himself to exactly the path the next enemy will come from and then to the next, the next...
- And other times when he is all alone and you come from behind a corner he waits long enough with firing so you could introduce yourself.
- Guards in Metal Gear Solid: Portable Ops are practically psychic. Even if you're playing as one of them, wearing the same face-obscuring uniform, with the same equipment, if anything suspicious happens, such as an explosion, they will instantly know you were behind it, even if it would be completely impossible for any of them to have seen you plant the bomb.
- In Mount & Blade AI does not have it's vision hurt by foggy/night battlefield. As the player is the only one that can use archers properly without Warband's AI upgrades (that is, put them on top of a hill and wait for the enemy), this tends to be in your favor.
- Oddly inverted in the obscure real-time strategy game Metal Marines, at least in the PC version. A side loses when all three of its "bases" are destroyed. Normally, the AI will ruthlessly attack any assets of yours it "discovers", but it will completely ignore any base hidden under a camouflage unit until one of its missiles, which it fires at random locations on your map, happens to hit its location. A human player, on the other hand, will recognize the distinctive camouflage unit icon and immediately target it with a missile. This particular bit of Artificial Stupidity turns the camouflage unit into a complete Game Breaker; you can just build a single missile launcher, fire it, let it get destroyed, and repeat this process until the AI no army left, because it never quite gets around to actually killing you.
- In Soldier of Fortune: Payback's final stage, "Club Evolution", the dancefloor's disco lights are blindingly bright to you, but they don't faze the Mooks one iota.
- Averted in Perfect Dark with the tranquilizer. When human players are hit, the screen goes blurry and it becomes hard to see. When the AI is hit, they essentially lose their ability to see entirely, resulting in them firing their guns at everything except you.
- Also in Perfect Dark, if you enter a lit area with your night vision goggles, it becomes blurry and impossible to see. In one stage, if the lights go out in a place where the female guards are wearing night vision goggles and you turn the lights back on, they are also blinded and are unable to shoot you.
- Oftentimes in Civilization, the computer will send out settlers to claim every strategic resource they can find before you can. This includes resources that only become visible later in the Tech Tree.
- It kind of does this for you as well. In Civ 4, at least, the game will suggest where to settle your city, and sometimes it is suggesting a place where you will find iron/coal/uranium/etc later on.
- Inverted in Guitar Hero III, which has a battle mode famous for its Interface Screws. In this game, the attacks actually cause the AI to screw up far more than a human player would. Go ahead: try the "raise difficulty" attack on an easy portion of a song. The AI will still miss half the notes, even if they all happen to be green.
- In the original Descent, the AI most prominently exhibits this asshole behavior on Insane difficulty. They can even track you if you have an Invisibility Cloak.
- In Company of Heroes the Computer AI can see through the fog, this means that AT Guns and Mortars are able to attack your units as long as you are in range.
- It's not as bad as it used to be though, the AI used to fire mortars at cloaked units.
- Operation Flashpoint has enemies that will shoot you. Without any chance to see even one pixel of them even if you look exactly in the direction you see the bullet coming from. This starts going downhill but continues anyway in the later games - it isn't until ARMA II: Operation Arrowhead that the AI finally plays fair (which is rather ironic, given that the expansion's Takistan doesn't have as much foliage for the AI to magically see you through anyway).
- In Operation Flashpoint, this trope is inverted for the effect "the AI sees perfectly through the night". Any AI soldier (except those wearing Night Vision Goggles) has his aiming and vision capacity very handicaped in night time... even when standing in a well-lit town or under a clear and starry sky (where a human player will see a lot better without Night Vision Goggles).
- Battlefield: Bad Company 2 has this as a moderate problem in the campaign. Any time there is something obstructing your view, it is basically non-existent to the AI. Dust? They see right through it. Snow? Fat chance that'll slow their snipers down. A SOLID CONCRETE WALL!? Haha, they know exactly where you are at ALL times, and if you try to hide there and regenerate your health they'll immediately pull out an RPG and break the wall down. This makes certain sections FAR more difficult than they should be.
- Perhaps as a nod to this, one of the most frequently used Glitch powers is a scanner pinpointing the exact location of the user (i.e: the human player) and his progress.
- In Fire Emblem games, (6 to 10), on fog of war maps the enemies will know where you are. Always. What makes this even more frustrating is the fact that if the player runs into an enemy (in a space they cannot see) the character that was moving cannot perform any other actions for that turn. Enemies can charge right into your characters and attack anyway, crossing this into My Rules Are Not Your Rules.
- In STALKER: Shadow of Chernobyl, once you blow your stealth, all nearby enemies will know where you are. Fortunately, this is fixed in just about every mod out there, except for Oblivion Lost, when the AI get incredible aim, and can see you from a hundred meters away in pitch darkness.
- Though it is somewhat averted, seeing how if you open fire on a group of enemies, but flank around, for example, the building that the they are in and enter through the back, they'll still be scrambling around near the front, trying to find you. In fact, when facing multiple enemies in close quarters, using this tactic is practically a requirement.
- In Unreal Tournament, AIs know when and where double damage and other valuable powerups spawn and will go for them immediately. In certain matches, this effectively means that you're forced into a metagame that revolves around continually monitoring those spots unless you enjoy facing enemies with a constant advantage on you. Good players often behave this way, too, which the AI is presumably designed to mimic.
- If you blow your cover in Splinter Cell, the enemies in the level will all know your position.
- Conviction refined this; enemies now fire and search Sam's last known position, allowing him to sneak around and flank them. Sam himself gains "Sonic Goggles" that let him see enemies through walls. In the very level he gets them, he faces foes armed with similar devices. Uh-oh.
- In World of Warcraft, Mobs can actually see you from behind. While yes, you could say they simply heard you walking, but they'll do it from about twenty feet away. But even worse than this? Mobs can see you through walls. As long as you step into their aggro range, a mob will come screaming at you, whether it makes any sense or not.
- In Eternal Champions, Xavier's Interface Screw spell is absolutely useless against AI opponents.
- Some old Battleship games fit this trope - you didn't know where the AI's ships were placed, yet for some reason, they knew where you placed yours. So imagine, to many players horror, that the AI absolutely never missed because it knew exactly where you placed your ships while you were left guessing as it hit every single one of your ships.
- Mostly averted in the Thief series, where stealth is the entire object of the game. However, one notable exception occurs in games 1 and 2 of the series, where if you alert an NPC and then hide in a dark area, the NPC will always end up walking directly towards your precise location while "searching".
- However, this can work out well. If you make some noise, you can move enemies out of areas that are dangerously lit up into the dark, where you're waiting with your trusty blackjack.
- Medal of Honor. This rears its ugly head in the Command Post, where the guards will clairvoyantly detect you sneaking in and sound the alarm (especially on Hard difficulty), and in Sniper Town, where the snipers have greater visual range than you and will instantly hit you the moment you step into their line of sight, and enemies in general will accurately chuck grenades from places where they shouldn't be able to see you. And once you tip off a guard in a Stealth-Based Mission, all the enemies in the level know it.
- Sometimes happens in poorly written computer poker games. If the computer makes large bets and multiple reraises while holding cards that are complete rubbish, and then proceeds to pull an improbable victory out of the draw - like if it bets huge on a 2-7 off-suit in Texas Hold 'Em and ends up with a full house, or replaces four cards in five-card draw and hits a straight flush - the odds are good that you're dealing with this trope, especially if you notice it happening multiple times per game. Another clue is if you notice the computer frequently drops whenever you get a strong hand, even if you bet minimally or not at all...as if it somehow knows it can't beat you.
- In Seven Kingdoms, the AI ignores Fog of War and unexplored areas, and always knows where everything is. This becomes especially noticeable when playing as Japan, as their Seat of Power lets them see when other players target their buildings — from the other end of the map, without ever having seen that civilization before.
- The hostiles in Minecraft are like this, but only after they've already spotted you the normal way. Then they can track your movement through any kind of wall and even explode from behind a thin wall. Results in Artificial Stupidity in that transparent blocks like glass count as walls, so mobs cannot see you through glass unless you've already been spotted through just air.
- Played straight with Spiders and their poisonous relatives Cave Spiders. They can sense you through walls.
- As soon as you reveal that there's an intruder in Deus Ex, even if you don't telegraph your position (say, by shooting somone in the head with a silenced pistol from behind cover), everyone comes running straight for you.
- In the sequel, since the Omar are a Hive Mind, if you kill one, the entire race turns against you.
- A particularly egregious example involves information only the player is supposed to have. It's bad enough the cops in Grand Theft Auto IV already manage to appear within their own line-of-sight of you just as you're getting out of their "arrest zone", but it becomes even more blatant when they appear specifically on a GPS route you've laid out for yourself.
- In Medal of Honor: Airborne, enemies know when you are scoped in while using a sniper rifle and move just out of the way. Paranoid Nazis.
- In Pocket Tanks, there are a number of weapons that will randomize a tank's gun angle and power. These are of course completely useless against AI tanks, which always know the angle and power for a perfect trajectory even in gale-force winds that switch direction every turn.
- In Hitman: Blood Money, if 47 must avoid or kill a rival assassin before they can kill him, said rival always instantly sees through 47's current disguise, no matter what it is or how low the alert meter is.
- In Just Cause 2, causing any sabotage will set off the alarm, no matter where you are, even if you caused the sabotage by setting off a C4 in the next island, and even if you did not even cause the sabotage to happen. However, even if they do know where you are, if they can't physically see and shoot at you while you're there, eventually they'll actually forget about you.
- Thankfully averted by the factions who are supposed to be allied with you, as they will call out to you while attacking military forces and ask for assistance, but only if they can physically see you. "Thankfully" and "supposed to be" mean that, if said military forces hear them, they'll then start to attack you too - and those other factions will take advantage of this just so you can't have a moment of peace, sending out one soldier to take on the 4+ elites guarding whichever propaganda trailer in the village you're currently looking for collectables in.
- In Fallout 3 being caught committing a crime or act of bad karma, such as pickpocketing, theft, murder, breaking and entering, or using the Mesmetron to enslave someone, will immediately alert all the people in the location and turn them hostile.
- Also, after getting a certain level of karma (either good or bad) you get hitmen sent after you. The first encounter is a scripted encounter that comes after you exit a metro station some time after attaining the required karma level. And they will find you. It doesn't matter if you're wearing the Chinese Stealth Suit at that moment, they'll walk right up to you and tell you they're going to kill you.
- A minor example in Fallout: New Vegas: using silenced weapons in hiding can let you get away with killing people, but killing certain high-ranking NPCs (generally major faction leaders like Caesar, or Pacer from the Kings) will always earn you infamy and make members of that faction or town hostile. Although the trope is in play with gameplay, it makes sense from a story perspective, as those characters are well guarded, so the player character is the only one with the opportunity and motive to kill them in the course of the game. The two major factions also send hitmen after you in scripted encounters ("The Caesar has marked you for death, ready yourself for battle!"); like Fallout 3, they always track you down once you enter their patrol areas, even if you are in Sneak mode.
- Inexplicably, the member of the Boomers using the artillery cannon can always tell where you are even if you're in hiding and using a Stealth Boy.
- At the end of the Dead Money DLC, if you try to shortcut out of the vault, Elijah will automatically detect you and reactivate the force fields and turrets.
- The Nightstalkers, Cazadores, Cyberdogs, and even Lobotomites in Old World Blues have ridiculously high perception that allows them to detect the player a half-mile away even when they have a stealthboy on.
- Redcoats in Assassin's Creed III are particularly good at tracking Connor through the busy streets of such bustling Colonial cities as New York and Boston, even if you dive under a fence, through a back yard, climb onto a roof and drop down onto the deck of a ship, you can bet at least one persistant Brit managed to follow you, and the rest are all figuring out another way to get to you. The only way to shake them is to either escape outside their search range, or to get out of their line of sight and dive into a hiding place, such as a pile of hay or cart full of greenery.
- In Test Drive Unlimited there's a 90% chance that if you hit a traffic car, the police will start looking for you immediately, even when there aren't any police cars in the area.
- The AI in Baldur's Gate is coded so that it always knows where your characters are, but isn't allowed to target any being outside its sight range or under an invisibility effect. This makes stealth completely useless beyond a certain level because the AI is programmed to counter invisibility effects inside its sight radius with the spell True Sight, which dispels all invisibility effects inside your sight radius. This means that when you enter a mage's sight radius while stealthed it will immediately cast True Sight and dispel it, revealing that the AI always knew you were there.
- 'DOOM'': Monsters that have been alerted to your presence will "know" where you are and attempt to get to you to attack regardless of where you are in the level, although this is mitigated by their lack of pathfinding A.I. If you enable monster visibility on the minimap, you can watch them bonking into wall like confused duckings trying to random-walk through a maze.
- In the Syphon Filter series, enemies can detect you in pitch blackness even if they lack night vision goggles.
- This is why winning a game of Microsoft Hearts is nigh impossible. Bad enough that the AI will gang up on you, they know what your cards are, and they know exactly which cards to play that will put you at disadvantage.
- Warframe has this as a gameplay element, in a sense. Enemies won't know you are nearby (and are pretty bad at noticing the technicolor ninja with glowing lights) at first, but if you are detected, the enemies in the area will all become alerted and react in this way- and if one of them reaches a terminal to activate an alarm it'll cause every enemy for the rest of the level to automatically know where you are once you enter their area. Additionally, bosses and their spawned minions are automatically "alerted".
- In the TV series ReBoot (which was set in a computer and involved the main characters trying to beat the user in uploaded games), hero Bob would often use his keytool to scan the game, which would tell him the game's details, the number of lives the User had, and where the User was at all times, effectively invoking this trope in-universe.