History Main / GoodBadBugs

** The fact that the NTSC color signal causes artifacting as a whole. Computer programmers were initially frustrated that it made text borderline unreadable at 80 columns with some color combinations due to the burst overlap causing blurring to the text, which doesn't happen on RGB monitors. However, they soon discovered that by carefully placing their pixels and choosing their colors, they could create colors that were never in the computer's palette to begin with. And the kicker is, this bug is a fault with the way NTSC signal works, meaning it was exploited by every single computer system with a color limitation but output to TV- documentations show that the trick has been used on the UsefulNotes/AppleII, UsefulNotes/Atari8BitComputers, UsefulNotes/{{Commodore 64}} and even [[UsefulNotes/IBMPersonalComputer PCs]]. Unfortunately, this didn't work for people in PAL regions as PAL was widely advertised to be immune of artifacting (although in truth, it was simply immune to the NTSC method- it has it's own color-mangling problem as outlined below).

** Similarly, for Pi Day one Wiki/{{Wikipedia}} admin tried to block another for 3.14159265359 seconds as a joke, [[https://en.wikipedia.org/wiki/Wikipedia:Village_stocks#SQL_for_the_Time-traveling_Block_Breaker_award but somehow ended up setting the block to expire in 1975, which the person on the receiving end of the block saw as expiring in 2021.]]

* ''VideoGame/KingsQuestVAbsenceMakesTheHeartGoYonder'': Play the DOS version with the CD for the Windows version in your disc drive. The game will try to read the audio files off of the disc... [[https://www.youtube.com/watch?v=RqunFIEI1IY the wrong audio files]]. You'll get entirely the wrong dialogue being played with entirely the wrong scenes, turning the plot into gobbledygook, in addition to sound effects replacing dialogue, dialogue bits replacing sound effects, songs from nowhere, hammers going "boo-boop" and rivers telling you to quit.

** In the original, the "random" point value of the flying saucer is actually a completely predictable function of how many times the player has fired. It is worth 50 points if hit with one of the first 8 shots, 100 points if hit with shots 9 10 11 or 12, 150 points if hit with shots 13 or 14, and 300 points if hit with shot 15; then the cycle starts over. A savvy player can count his shots and get 300 points each time.

* ''VideoGame/{{Sinistar}}'' has a bug that allowed you to acquire 255 ships. It takes a second or two for the Sinistar to eat your ship, during which a Warrior ship can shoot you, making you lose two lives at once. If you start with one life, your number of lives will drop from 1 to 0 to -1. Since this number is stored as an [[UsefulNotes/PowersOfTwoMinusOne 8-bit unsigned integer]], -1 will register as 255.

* ''VideoGame/ResidentEvil4'' had several that were BoringButPractical such as running at 1.5 times Leon's normal speed by switching to the [[ShotgunsAreJustBetter Striker]], raising it and then quickly equipping another weapon before the laser sight could activate ([[http://speeddemosarchive.com/ResidentEvil4.html useful but cautiously used]] in {{speedrun}}ning). However, the most memorable is Ashley's ability to [[TookALevelInBadass suplex enemies]] by [[https://www.youtube.com/watch?v=d0Tg1btDrMA whacking them with a door]]. It's also possible to open locked doors from the wrong side with the TMP equipped to bypass entire "find the key" {{Fetch Quest}}s, pressing L + R before every PressXToNotDie moment which (most of the time) makes the other button prompt appear, and being able to push Ashley through the scenery by getting her into a corner and pushing against her when she ducks (useful for keeping enemies off of her). Also, the gimmick where Ashley scolds you for looking up her skirt is literally set to trigger ''anytime'' Leon's eyes aim up in that direction - even when he's been knocked down by an enemy or his [[SugarWiki/FunnyMoments severed head rolls between her legs]].
** ''VideoGame/ResidentEvil5'' had a glitch where you could load guns using the inventory... even if they were the gun you had out. In multiplayer, this allowed skilled players to reload near instantly, circumventing the weakness of many weapons and making chaining combos together a lot easier.

* ''VideoGame/{{Splatoon|1}}'' had a glitch on the Piranha Pit map where, due to object placement in some modes, you could bend your Inkling's neck beyond any sane angle. This happened because the game had no code specifically to handle Inkling posture when attempting to enter a niche shorter than they are tall (which could only happen on that map).

** Using the "Shrink Ray" on summonable terrain features like the "Hole" creates gaps that it's possible to escape the stage through.
** Terrain features containing water (like the "Sea") can buoy floating objects in themselves without being placed down. This can even be used to carry [[PlotCoupon Starites]] in things such as ice blocks to you!

** The physics engine is decidedly fickle, and known for producing its fair share of bizarre (and hilarious) spazz-outs. Just for starters, objects made with lots of other objects (e.g., sticking together with glue) have a tendency to "creep" along the ground with steady momentum. Sticking too many things onto something Maxwell can pick up (like a BASEBALL BAT) can result in him being flung across the screen when the creation explodes.

** If you attach one end of a rope to an object and move the other end of the rope to a container, you not only have the option of attatching the rope to the container, but also the additional option of putting the rope inside, which also puts the attatched item inside. You can instantly win almost any level where the starite is visible from the start by spawning a container next to the starite, attaching a rope to the starite, and puting the rope and starite inside the container and drag the container all the way to Maxwell instantly. Living things can also be put into containers this way, thereby allowing Maxwell to avoid enemies entirely and/or keep vital NPCs out of harm's way by attatching rope to them and stuffing them into refridgerators.
*** Another rope-related glitch is the classification of attached objects as one object. Basically, if you attach two objects together via rope, they can pass through each other, meaning that you can attach a starite to a gate and then have it fall through to the other side of the gate.
** Attaching an object that causes other objects to gain momentum with one of those items using a rigid body (like glue and planks) yields [[https://www.youtube.com/watch?v=JPQN6V-j2u8 hilarious results]]
*** This includes the "flying bridge" glitch, where using a fishing rod on a bridge Maxwell is standing on causes him to fly to the ceiling or off the screen, where he dies.

** Similar to glue, rope and related objects can create numerous glitches. You can instantly win almost any level by spawning a container next to the starite, attaching a rope to the starite, and then attaching the other end of the rope to the container, which allows you to put the rope and starite inside the container and drag the container all the way to Maxwell instantly.

* ''VideoGame/DMCDevilMayCry'' has multiple glitches that make Dante fly around the screen avoiding enemy attacks, bosses that are unwilling to attack or are just paralyzed. The fandom decided to use them [[https://www.youtube.com/watch?v=pFLUE2kdemE to have fun.]]

* ''VideoGame/{{Splatoon}}'' had a glitch on the Piranha Pit map where, due to object placement in some modes, you could bend your Inkling's neck beyond any sane angle. This happened because the game had no code specifically to handle Inkling posture when attempting to enter a niche shorter than they are tall (which could only happen on that map).

** In Salmon Run, if a round ends with a team wipe, the game doesn't formally end the round until the final player's death animation finishes. Players quickly discovered that the game's drowning animation was a few seconds longer than the normal death animation, leading people to deliberately jump off the stage in the last few seconds of each round, guaranteeing that the clock would run out before their death registered.

* The original Japanese version of the NES port of ''VideoGame/Ghostbusters1984'' has a glitch where the Ghost Alarm sells for more than it actually costs, easily allowing the player to repeatedly buy it and sell it back repeatedly for unlimited money.

* [[https://ki-no-shirayuki.dreamwidth.org/18419.html A selection of several cases from]] ''VideoGame/ToukenRanbu'', which includes such gems as swords saying other swords' lines, swords turned into [[AttackOfTheFiftyFootWhatever giants]], an enemy being the MVP and, in a chilling moment of BreadEggsMilkSquick, a sword who has only sustained serious damage being displayed as dead.

[[folder:Stealth-Based Games]]
* VideoGame/MetalGear series:
** The NES version of the original ''VideoGame/MetalGear1'' had a glitch when you entered the computer room, if you went immediately right you would glitch into the final boss room without having to blow up the computer. This was helpful if you didn't rescue the professor (even though you ''knew'' you needed plastic explosives to destroy the computer, the game won't let you unless the professor told you).
** ''VideoGame/MetalGearSolid'' had the Instant Elevator bug. Rather than wait after calling an elevator, if you hit the button again it would arrive ''instantly''.
*** It also has the Vent Glitch used by speedrunners. Switching to first person view while in a specific position in a specific vent causes Snake to go out of bounds. Guiding him then to certain spot causes a cutscene to be triggered that advances the story to the part where [[spoiler:Snake has been captured]], allowing him to skip 5 bosses, at the cost of having a shorter lifebar.
*** There is also [[https://www.youtube.com/watch?v=YBQShydrjmo&feature=youtu.be this rather difficult to explain glitch]] that allows you to get up close and personal to Sniper Wolf in ''both'' battles. Normally if you try to get too close you are hit by a scripted, unavoidable attack that pushes you back several feet, but through a specific glitch involving a grenade and a ration you can render yourself immune to it, run right up, and punch her to death as she [[AIBreaker helplessly strafes around still trying to snipe you]].
*** Though it's less of a glitch and more of an exploit, the developers not disabling the radar in the snowfield the second Sniper Wolf battle takes place in allows you to use Nikita missiles on her. As they only expected you to use the [=PSG1=], she's not programmed to avoid, shoot down, hide from, or in any way respond to the missiles, allowing for an absolute ZeroEffortBoss.
** ''VideoGame/MetalGearSolid2SonsOfLiberty'':
*** Raiden has invincibility frames when he pops out from a corner and aims his pistol. If you get the timing down, you can outright NoSell attacks from enemies by hopping out, firing a round, hopping back, and repeating. This is one of the most effective ways to battle Fortune and the Harrier, as you can just stand there like an arsehole dry-firing an empty pistol while they ineffectually spam you with their attacks.
*** There is one bug which, when combined with an AntiFrustrationFeature, allows you to skip the ''entire'' HoldTheLine battle where Raiden and Snake have to hold off waves of [[DemonicSpiders Arsenal Tengu]]. Before it begins go ahead and sucker-punch Snake a couple of times so he decks you back and you have less than half health, as you having low health will make Snake use his M4 Carbine instead of the USP during the battle. That's the legit part. Then, grab an Arsenal Tengu in a chokehold and drag him outside the room (through the door you came in) and choke him just ''once'' every single time he struggles, keeping him alive as long as possible. For some reason, as long as you're doing this, all the other Arsenal Tengu will leave you alone and target Snake, who can hold his own no problem with his M4. Then when the one guard finally goes down, take down the one next guard who comes in and the fight ends. You finish ''the entire battle'' by only taking out two enemies.
** ''VideoGame/MetalGearSolid3SnakeEater'':
*** Cardboard is fireproof. Yes, by wearing the cardboard box you won't take damage from flames and can't be lit on fire, and even if on fire donning a box will put it out. The only thing that can hurt you is a direct blast from a flamethrower, and even ''that'' can't light you on fire. The glitch is because the developers never bothered to program an animation for Snake burning while in the box, presumably because [[ViolationOfCommonSense they never assumed anyone would be dumb enough to use cardboard to shield from fire]], and thus the game just ignores it.
*** When you pull the pin of a grenade there is a ''very'' brief window where Snake becomes both invisible and silent for all intents and purposes. With careful timing you can basically just run in front of guards without them noticing you and, since it's possible to put grenades away without throwing them, with practice you can just gallumph through entire areas without triggering alerts.
** In ''VideoGame/MetalGearSolid4GunsOfThePatriots'', a glitch with the long-barreled and scoped version of the Desert Eagle means the magazine he grabs to reload the weapon with is inside ''another'' long-barreled and scope Desert Eagle, which he duly inserts into the space occupied by the first. It helps if you exclaim "my deagle needs more deagle!" while doing this.
* In VideoGame/ThiefTheDarkProject there are underground giant bipedal lizards called burricks, which can be dangerous because they emit poisonous gas. While the game was still in development, though, bad coding led their attack to not have any range. That means, the gas was released on their place, damaging them, leading to what the developers commented as "farting to death". It was so humorous that they added it back in a special secret level for Thief Gold, dedicated to show to players the bugs and the scrapped ideas before game shipping with with comments from the team.
* ''VideoGame/YandereSimulator'' has [[GoodBadBugs/YandereSimulator its own page]].
[[/folder]]

* GoodBadBugs/{{Roguelike}}

* An as-of-yet unreplicatable glitch in ''Pinball/WHODunnit'' causes the elevator doors to remain open for the rest of the game. Not only does this allow easy access to modes available only on certain floors, but the shot into the elevator is by far the easiest and safest shot in the game. The discovery of this glitch in 2015, twenty years after the machine's debut, got it banned from all high-level tournaments due to its exploitability once activated. It was then later discovered that an ''earlier'' version of the software was immune to this glitch.

* Certain more recent ''VideoGame/{{Tamagotchi}}'' models have [[https://web.archive.org/web/20110623023638/http://www.pixelmood.com/tamagotchi_connection_debugging.htm a trick]] with a pencil and a screwdriver that lets you access the device's debug menu, which allows you to choose any pet you want, including those that were DummiedOut.

* In ''VideoGame/CryptOfTheNecroDancer''', there is an uncommon bug involved with the tempo switches on the floor. If you set one off, and blow it up before it reverts, the music will ''stay slowed down/sped up'' for the remainder of the level.[[labelnote:*]]Can either be an EasyLevelTrick or a SelfImposedChallenge.[[/labelnote]]

** The fact that the NTSC color signal causes artifacting as a whole. Computer programmers were initially frustrated that it made text borderline unreadable at 80 columns with some color combinations due to the burst overlap causing blurring to the text, which doesn't happen on RGB monitors. However, they soon discovered that by carefully placing their pixels and choosing their colors, they could create colors that were never in the computer's palette to begin with. And the kicker is, this bug is a fault with the way NTSC signal works, meaning it was exploited by every single computer system with a color limitation but output to TV- documentations show that the trick has been used on the UsefulNotes/AppleII, UsefulNotes/Atari8BitComputers, UsefulNotes/{{Commodore 64}} and even [[UsefulNotes/IBMPersonalComputer PCs]].

** In the original, the "random" point value of the flying saucer was actually a completely predictable function of how many times the player had fired. It was worth 50 points if hit with one of the first 8 shots, 100 points if hit with shots 9 10 11 or 12, 150 points if hit with shots 13 or 14, and 300 points if hit with shot 15; then the cycle started over. A savvy player could count his shots and get 300 points each time.
** When the game was originally designed, the amount of sprites on the screen seriously lagged the system. The more invaders you killed the more game sped up, inadvertently creating the idea of DifficultyByAcceleration.
* ''VideoGame/{{Sinistar}}'' had a bug that allowed you to acquire 255 ships. It takes a second or two for the Sinistar to eat your ship, during which a Warrior ship can shoot you, making you lose two lives at once. If you started with one life, your number of lives would drop from 1 to 0 to -1. Since this number was stored as an [[UsefulNotes/PowersOfTwoMinusOne 8-bit unsigned integer]], -1 would register as 255.

* In the ''Combat'' game packed in with the original Atari 2600, running your tank into the inside of a corner--usually a corner of the screen--would teleport you to the opposite side.

* In the original ''VideoGame/EscapeVelocity'', one could suppress planetary defense fleets entirely by hiring enough escorts to achieve the {{cap}} on the number of ships in a system.

** In ''VideoGame/MetalGearSolid3SnakeEater'', when you pull the pin of a grenade there is a ''very'' brief window where Snake becomes both invisible and silent for all intents and purposes. With careful timing you can basically just run in front of guards without them noticing you and, since it's possible to put grenades away without throwing them, with practice you can just gallumph through entire areas without triggering alerts.

** ''VideoGame/MetalGearSolid2SonsOfLiberty'' has a bug which, when combined with an AntiFrustrationFeature, allows you to skip the ''entire'' HoldTheLine battle where Raiden and Snake have to hold off waves of [[DemonicSpiders Arsenal Tengu]]. Before it begins go ahead and sucker-punch Snake a couple of times so he decks you back and you have less than half health, as you having low health will make Snake use his M4 Carbine instead of the USP during the battle. That's the legit part. Then, grab an Arsenal Tengu in a chokehold and drag him outside the room (through the door you came in) and choke him just ''once'' every single time he struggles, keeping him alive as long as possible. For some reason, as long as you're doing this, all the other Arsenal Tengu will leave you alone and target Snake, who can hold his own no problem with his M4. Then when the one guard finally goes down, take down the one next guard who comes in and the fight ends. You finish ''the entire battle'' by only taking out two enemies.