History ThrowItIn / VideoGames

** In ''VideoGame/{{Metal Gear Solid 4|GunsOfThePatriots}}'', [[HonestJohnsDealership Drebin]]'s pet monkey was thrown in for two reasons. One, they realized that Raiden's motion capture actor did a pretty good imitation of a monkey. Two, Kojima felt that Drebin was too bland a cahracter without some kind of gimmick..

* The 2009 ''VideoGame/BionicCommando'' game features an EasterEgg where you can listen to one of Super Joe's flubbed lines. If you die on a certain boss in the game and try again, instead of telling Nathan to fight the boss, he tells him [[https://www.youtube.com/watch?v=XLVYkz5WEio&t=1m10s "You'll just have to fuck it"]].

* ''VideoGame/EarthBoundBeginnings'': [[http://www.lostlevels.org/200407/200407-earthbound2.shtml The running feature]] in the English version of the game was originally added in for debugging purposes, hence why it simply doubles the game's overworld speed (causing NPCs to move faster too). Localization director and English scriptwriter Phil Sandhop convinced the development team to leave it in the final game, due to how slow and plodding it was otherwise. A more conventional run feature that only affects the player's overworld speed was included in both the ''MOTHER 1'' half of ''[[CompilationRerelease MOTHER 1+2]]'' and ''VideoGame/{{MOTHER 3}}''.

** The classic ''VideoGame/SpaceInvaders'' gradual speed-up of the invaders, as more are shot, was a GoodBadBug resulting from the programmer pushing late 1970s hardware to its limit. It allowed the game to gradually get harder, creating the idea of difficulty curves.

** One such example that's not ''just'' an AscendedGlitch, but also a ShoutOut: ''VideoGame/IWannaBeTheGuy'' has a bug that makes it possible to skip [[Franchise/{{Metroid}} Kraid]][[VideoGame/StreetFighterII gief's]] second phase before he rises up, which makes the rest of the battle a total pushover since he's at a much lower height and thus much easier to shoot. WordOfGod says it was kept in "since it works just like Kraid from ''VideoGame/SuperMetroid''", where it's possible to kill him before he rises up to his full height and breaks the ceiling if you shoot multiple Super Missiles in his mouth in rapid succession.
** ''{{VideoGame/Tribes}}'s'' uniqueness was born of this -- in the first game, "skiing" was a glitch based on clever usage of the jetpack to go really damn fast. After the bug was fixed and then put back in due to fan outcry, it became the series' calling card, and in its revitalization ''VideoGame/TribesAscend'', it's not only a game mechanic, but '''the''' game mechanic -- the new user guide demonstrates walking, shooting, jetpacking, and skiing. You only pass if you can ski moderately well. The game is advertised as the fastest modern shooter.

** ''VideoGame/{{Deltarune}}'' is no stranger to this. Infamously, there was a stray pixel in the fight against King, so of course Toby Fox did the sensible thing and [[TrollingCreator added one to Queen's battle]] as well.
*** [[TrollingCreator And added two more to the King fight during the Undertale anniversary Deltarune livestream for good measure.]]
*** Then there's the Chapter 2 {{superboss}}: [[spoiler:Spamton NEO turns your SOUL yellow, marking the first time a SOUL color change occurs in ''Deltarune'', while also introducing a ChargedAttack. A glitch was quickly discovered where players could rapid-fire this attack, and rather than patch it out, Toby instead had the boss progressively [[TurnsRed turn red]] the more you use it.]]
* When creating the character model for ''Franchise/TombRaider'''s Lara Croft, creator Toby Gard was trying to make a minor adjustment to Lara's breast size. He selected all vertices in the breast to resize them, but the mouse slipped and they increased 150%. [[MostGamersAreMale The team loved the new look]] and Lara's famous physique was born.
* The ridiculously long scarf worn by Hotsuma in the [=PS2=] ''VideoGame/{{Shinobi}}'' is a result of a programmer gag: originally it was a normal-length one, but someone made it a lot longer, everyone liked it and they proceeded to make it even longer.

*** Ocelot's trademark hand gesture was an improv by the motion capture actor that made everyone laugh so hard it became one of his signature traits.
*** To create a more realistic performance, Creator/HideoKojima had the motion capture actors for Naked Snake switched so that the one who specialized in action sequences did the dialogue scenes, and vice versa. In one scene, EVA leans in to kiss Snake, and Snake's actor, not used to doing romantic scenes, nervously edged away. They kept it in since the response was cute and fit Snake's character perfectly.
*** When Snake's watching the altercation at Groznyj Grad through binoculars, the characters all storm off in different directions. There's no button prompt to indicate that you can do it, but using the First Person View mode during this scene and looking to the far right shows Tatyana imitating Ocelot's signature hand-gesture and cracking up. Her motion capture actress was messing around thinking she was off-shot when she did it. The team also liked the idea of other characters mocking Ocelot for his hand gesture that they added another secret first-person scene where The Boss imitates it in a later cutscene.
** In ''VideoGame/{{Metal Gear Solid 4|GunsOfThePatriots}}'', [[HonestJohnsDealership Drebin]]'s pet monkey was thrown in when they realized that Raiden's motion capture actor did a pretty good imitation of a monkey. That, as well as the fact that Drebin seemed too bland by himself in Kojima's eyes.
* ''VideoGame/WiiSports'' was originally set up to be a ''[[Franchise/SuperMarioBros Mario]]'' title. The test audience surprisingly preferred the Miis.
* One of the levels of ''VideoGame/{{Portal}}'' can be finished in [[https://www.youtube.com/watch?v=_2qiGe-OYLc mere seconds]], by using shortcuts to skip the entire level. When playtesters figured this out, the developers decided to keep it, since only advanced players would know how to utilize it. In fact, in the advanced versions of that chamber, the qualifications for gold medals require that you do this. The commentary put it like this: If the exploit takes more skill and ingenuity to perform than doing it the intended way, it's perfectly reasonable to keep it in.

** For anyone wondering why [[spoiler:the Space Core is the only corrupted core to speak after being attached to Wheatley]], it was thanks to an outburst by Creator/StephenMerchant (the voice of Wheatley) after hearing Nolan North recording the lines for the Space Core. The developers thought it was ''hilarious'' and just had to find a place to put it in:

* [[http://www.telltalegames.com/forums/showpost.php?p=224468&postcount=11 According to Dave Grossman]] Guybrush Threepwood's first name came when ''VideoGame/MonkeyIsland'' was in development. Since he had no name yet, his character art was simply named "Guy", and when Steve Purcell, the artist responsible for "Guy's" sprite, saved the file, he added "brush" to the end, to indicate that it was the Deluxe Paint brush for Guy, creating a file called "guybrush.bbm". They eventually just went with that, and had a great deal of fun [[LampshadeHanging commenting]] [[RunningGag on his weird]] [[AccidentalMisnaming name]].

** The name of the god Armok was taken from a variable used in the game's predecessor [[http://www.bay12games.com/armok/ Slaves to Armok: God of Blood]] standing for the number of available arms: arm ok.
** Working on the necromancy implementation for DF 2012, Toady discovered that he could accidentally cause necromancers to raise undead from skins, hair, and other waste tissue, in addition to more conventional undead. He decided this made as much sense as the walking skeletons did, and published it in his development log as one of the new features.

** The "Prelude" (a.k.a. the "Crystal Theme") is quite possibly the most iconic song in the series. It was put together by Creator/NobuoUematsu in ''ten minutes''.

*** Kefka's infamous introduction scene (barring the flashback) was not in the original script. Originally, he was intended to simply arrive at Figaro Castle and demand for Terra. However, Yoshinori Kitase felt that the scene was too boring to make completely normal, especially when they had only Amano's artwork of Kefka to work with, so he added in a scene where Kefka is complaining about Gestahl sending him off to Figaro, in the desert, on a reconnaissance mission, and then stating that there is sand on his boots, causing the soldiers to wipe the sand off, and then, after {{laughing ma|d}}niacally, berates them as idiots, with the intention of giving the implication that Kefka may be missing a screw or two from his head. They kept it in, and this also resulted in Kefka's characterization that we know him by to this day.
*** On the subject of Kefka: "[[SugarWiki/AwesomeMusic Dancing Mad]]", Kefka's final boss theme for which LaughingMad was named. Not so much that the song wasn't meant to be, but ''how much there ended up being of it'', was a complete throw-in by Uematsu, as revealed here:

*** An in-universe example of this was used. Ultros, feeling sore about his earlier defeat, decides to get his revenge by dropping a 4 ton anvil on top of Maria/Celes, but had a five minute delay due to his miscalculating the amount of strength and time he needs to actually attempt to push it onto Celes/Maria, giving Locke and the rest of the Returners (who discovered Ultros' plot due to a note in the dressing room for "Maria") enough time to halt his plan. Unfortunately, they also ended up interrupting the play by knocking out two key actors in the opera production (Draco and his rival suitor for Maria), resulting in Locke and the returners improvising, with Locke trying to do his best (even if abysmal) attempt at mentioning that he'll take Celes'[[note]]The opera's character is named Maria, but Locke, horrible actor that he is, uses the actress's name instead[[/note]] hand and not Draco or Ralse, and Ultros challenging Locke to a duel.
** ''VideoGame/FinalFantasyVII'': Famously, "[[SadBattleMusic Aerith's Theme]]" is played throughout the battle with Jenova-LIFE and the subsequent scene of [[spoiler:the team paying their respects to Aerith before her body is submerged into a lake]]. According to the developers, it wasn't supposed to; the music was meant to only play during the scene where [[spoiler:Jenova impales Aerith]], but a bug caused the music to override Jenova's theme for the boss battle. They ended up liking the accidental symbolism, and decided to leave it as it is.

*** One of the mounts players can earn in PVP is the ADS mount, which is a giant metallic sphere. The idea came from a fan during a fanfest and the developers found it so hilarious that they threw it in.

** Most of Kefka's dialogue in ''VideoGame/DissidiaFinalFantasy'' was actually ad-libbed by his Japanese voice actor, Creator/ShigeruChiba, and his tendency to change the tone of his voice mid-sentence was also due to Chiba.

** Before the production of ''VideoGame/KingdomHeartsBirthBySleep'', Sora's Japanese voice actor jokingly whined about having to voice TheHero all the time and asked if Nomura couldn't give him a few more "evil" lines. And so, Nomura created [[spoiler: Vanitas, the EnemyWithout of Ventus and TheDragon of ''Birth by Sleep'', giving the actor plenty of "evil" lines to work with from Vanitas being the darkness of Ven's heart made manifest]].

** Prior to patch 1.8, if you went an extremely-far distance in your Minecraft world (12,550,820 in-game meters, or roughly 820 hours of straight walking), the terrain would suddenly become severely distorted and laggy due to a glitch in the way in-game worlds were generated. The fans dubbed the phenomenon "the Far Lands" and framed it as a mysterious place where reality is distorted. Notch said he liked the idea of this mysterious place, so instead of fixing it, he kept it in. However, patch 1.8 changed the world generation algorithm and accidentally removed the Far Lands. A somewhat different, and this time intentional, version of the Far Lands now exists in the Bedrock Edition. It's even part of Telltale's ''VideoGame/MinecraftStoryMode'' in the fourth episode.
** While Notch was creating the model for the pigs, he accidentally stretched the cube representing its torso vertically rather than horizontally. He thought it looked creepy and cool, and eventually turned it into a new type of monster called a [[MascotMook Creeper]].
* ''VideoGame/{{Warcraft}} 3: The Frozen Throne'''s Pandaren were originally an April Fool's joke that people responded to, so they were thrown into the game, with a side mission and a hero in the orc campaign. Blizzard even gave their race a tidy backstory and are a playable race in ''VideoGame/WorldOfWarcraft: Mist of Pandaria''.
* In ''VideoGame/QuestForGloryIV'', every evening in the Inn there are three villagers who convene. The voice actors had great fun ad-libbing lines for them, including a rant on how one of them used to be an elephant herder (the game is set in a country based on rural medieval Romania, filled with forests and swamps) but the elephants all started dying out. The ad-libbing is quite apparent as on many occasions their speech do not even match what's written in the dialogue boxes. At one point the characters even speak ''out of order'' of what's being seen at the screen. The story passed around is that the diskette version (which had no voice) was finished before the CD edition, which had voice acting. The developer loved the ad libbing that the voice actors did so much that they were not only allowed to continue but were used in place of the conversations in the diskette version, which is why they don't match.
* In the game ''VisualNovel/PlumbersDontWearTies'', there is a scene where the male protagonist {{narm}}fully flubs a line leading the crew members off screen to laugh about it. And they decide to leave it in anyway. WebVideo/TheAngryVideoGameNerd points it out, although you may want to keep [[https://www.youtube.com/watch?v=O4q6-7CiU0w#t=54s this link]] in mind.

** The very first game was originally envisioned as a fairly straight-laced street racer, until a bug in the cops' AI caused them to try and ram the player off the road instead of arresting them. The team liked it so much the game was repeatedly tweaked to make it fit, with the final product being a crime simulator that birthed an entire genre.
** In ''VideoGame/GrandTheftAutoIII'', the pedestrians have a strange habit of jumping in front of the vehicle you're driving - this was originally a glitch in the AI that the developers found quite funny.
** In ''[[VideoGame/GrandTheftAutoSanAndreas San Andreas]]'', planes will occasionally crash for no reason, a result of a less-than-airtight approach to random generation of flight paths that allows the possibility of planes' trajectories intersecting with the ground. It was kept because it added to the hilariously crapsack nature of the game.
** ''VideoGame/GrandTheftAutoV'' had its key actors perform many cutscenes with motion capture suits on and delivering dialogue live (leading to the realism of the CGI). In one sequence, Steven Ogg, the voice and mo-capper was supposed to vault over a low fence but he goofed and tripped over instead, causing the actor playing Franklin, Shawn Fonteno, to break into laughter. Rather than cutting the scene, Steven Ogg proceeded to deliver an epic (and somewhat scary) angry rant, in character, that was considered so good (along with Fonteno wisely also staying in character) that it was incorporated into the cutscene as it appeared in the game.[[note]]Only a tiny part hints that it's improv; Trevor says "motherfucker" which he normally doesn't as he takes insults involving his mother [[BerserkButton VERY seriously.]][[/note]] As a bonus, Trevor's ad-libbed rant actually worked towards the continuity of the game because [[spoiler: at this point in the game, Trevor had just left his friend Michael to, he thinks, be killed by Chinese mobsters, and his rant ties into the guilt the character is feeling about this.]] The scene ended up being one of the funniest in the game. [[https://www.youtube.com/watch?v=gCQ093vh3FM Watch it here]].

** Early concept art for the Draenor version of Shadowmoon Valley depicted the zone at night. The visual was so striking the team decided to make the entire zone permanently nighttime.
* Most of the swearing in ''VideoGame/BrutalLegend'' (especially on the part of Ozzy Osbourne's character) wasn't in the original script. Tim Schafer decided to keep it because it fits.
* Apparently when Fawful's dialogue was being translated for the English release of ''[[VideoGame/MarioAndLuigiSuperstarSaga Mario & Luigi: Superstar Saga]]'', several translation errors were noticed but kept in the game anyway since Nintendo of America figured it would still be in character for someone like [[IntentionalEngrishForFunny Fawful]] to say.
* The 2009 ''VideoGame/BionicCommando'' game features an EasterEgg where you can listen to one of Super Joe's flubbed lines: If you die on a certain boss in the game and try again, instead of telling Nathan to fight the boss, he tells him [[https://www.youtube.com/watch?v=XLVYkz5WEio&t=1m10s "You'll just have to fuck it"]].

* ''Franchise/{{Pokemon}}'': Prior to the release of ''[[VideoGame/PokemonRedAndBlue Red & Green]]'', one of the developers realized that, once he took the developer's tools out, there was room for one more mon. Since there were in-game references to the Pokémon Mew (where they got the material for Mewtwo), he decided to make it playable, but without a way to get it. No information was given about it, because except for the higher ups at Game Freak, ''no one knew you could get Mew''. He figured they could give it away later, and a tradition was born. The Mew glitch, discovered in 2005, allows you to get it normally by fooling the game into making it appear. This is due to the way the game handles numbers as code.

*** The gunships firing at [=RPGs=] launched towards them as opposed to the player was originally an unintended consequence of the simple way gunships determine what to shoot at (they're told to attack the "most dangerous target", which is ''supposed'' to be the player, but an RPG getting close to it is flagged as an even bigger threat than the player). Valve realized it added an extra challenge to the gunships and left it in.
*** A similar case during playtesting. At one point in ''Episode Two'', you're gently prompted into throwing a grenade into a dumpster full of boxes. Do this the first time and the Fast Zombie hiding in there will [[ItCanThink toss it back out]]. It was originally a physics glitch caused by the boxes that would fly out when the Fast Zombie emerged, but like Dog's IndyPloy, it was well received and left in.
*** Yet another random mistake ended up becoming a gameplay element: the Combine helicopter's infamous "mine spam" attack was originally inspired by one of the programmers accidentally making the helicopter shoot mines instead of bullets out of its machine gun, which slowed the game to a crawl; for the release they added a toned-down version of this as a DesperationAttack.
** ''VideoGame/HalfLifeAlyx'': The ability to cover your mouth to stop Alyx from coughing was inspired by playtesters. "Jeff" is a level where you must navigate around the titular mutant PlantPerson, who is blind but attracted to sound. The addition of spore clouds that make Alyx uncontrollably cough was a relatively late addition as a means of introducing another environmental hazard to the level. The developers then observed players trying to cover their mouths to protect Alyx, and this was made an actual feature shortly afterwards. This turned out to be an excellent addition to the level's horror atmosphere; as covering your mouth requires using one of your hands, carrying items become much more tense as a result.

** Samus Aran was originally going to be a man, and is even referred to as such in the original instruction manual. One of the developers thought it would be funny if the player found out she was a woman at the game's end. Somebody agreed, and [[SamusIsAGirl the rest is history.]]
** The manual for the original ''VideoGame/{{Metroid|1}}'' lists an item called the Barrier Suit, which simply decreases enemy damage. An item called the Barrier suit wasn't in the game; instead we got an item called the Varia suit, which did the same thing. The name actually came from a translation error: the Japanese version called it the バリアスーツ, baria su-tsu, which could be translated phonetically to varia su-tsu. The name, however, stuck with fans, and when ''VideoGame/MetroidIIReturnOfSamus'' came out, the manual said that an item called the "Varia" allows the activation of the Barrier Suit. When ''VideoGame/SuperMetroid'' came out, they just did away with all the rejustification, and from then on, the item was just called the Varia Suit.
* In ''VideoGame/SamAndMaxFreelancePolice: The Devil's Playhouse'', one part in the script asked for some characters controlling the body of a giant {{Kaiju}} monster to make it do an "anime pose", intended as an homage to ''Anime/{{Voltron}}''-type anime. The animator in charge of making the pose innocently asked the writer, "You mean like ''Franchise/PowerRangers'' or like ''Anime/SailorMoon''?", to which the eavesdropping person in the neighboring cubicle immediately popped his head over the side and said "Oh my god, make him do 'Sailor Moon'". As a result, instead of doing a ''Voltron'' pose, the monster does a version of Sailor Moon's TransformationSequence, which is a total non-sequitur but really, really funny.

* In ''VideoGame/SuperSmashBrosMelee'', the [[GoodBadBugs wavedashing technique]] was noticed early on. It wasn't so much thrown in as it was ignored because it was seen as harmless and the team was already struggling to finish the game on time. Then, its [[TournamentPlay real potential]] was discovered, and creator Masahiro Sakurai started to see it as [[CreatorBacklash not-so-harmless]]. It was [[ObviousRulePatch ripped out]] of ''[[VideoGame/SuperSmashBrosBrawl Brawl]]'' as soon as possible, and while ''[[VideoGame/SuperSmashBrosForNintendo3DSAndWiiU Smash 4]]'' onwards would attempt to acknowledge the tournament scene a bit more, wavedashing has never been seen since.

* [[https://screenrant.com/facts-you-did-not-know-bioshock-franchise/ Apparently]], Sheryl Lee of [[Series/TwinPeaks Laura Palmer]] fame ended up in the recording studio for ''VideoGame/BioShock2'' due to a scheduling mishap (likely due to confusion with Sheryl Lee Ralph, the voice of Grace Holloway). She was given a role as a Baby Jane splicer in the Atlantic Express, discussing Jack's whereabouts.
* ''VideoGame/SuperRobotWars'': Elzam's {{Leitmotif}} always being played when he's in combat was initially a programming bug (as he was a boss that switched to your side, and boss themes have higher priority than player themes; the bug was that when he switches sides, player theme priority is added onto his boss priority rather than replacing it). Since then, it seems both fans and developers loved it, making [[MemeticMutation nothing able to override Trombe!]], save for [[SourceMusic music actually playing in-universe]].
** In ''VideoGame/SuperRobotWars30'', there are some times where [[Anime/CodeGeass Lelouch]] will scream out "SHIN ZERO BEAM!" when he uses the Gekkouei-Sui's Absolute Zero Beam, as if he's a Super Robot pilot. That's because his voice actor, Creator/JunFukuyama, had ad-libbed it for kicks and the creator of the series loved it so much he allowed it to stay.

** As it turns out, Link's upgrade to {{Bishonen}} status between ''[[VideoGame/TheLegendOfZeldaLinksAwakening Link's Awakening]]'' and ''[[VideoGame/TheLegendOfZeldaOcarinaOfTime Ocarina of Time]]'' was the result of an [[https://web.archive.org/web/20210709060036/https://iwataasks.nintendo.com/interviews/#/3ds/zelda-ocarina-of-time/1/7 offhand comment made by the wife of one of the developers.]]
** Link's pink hair in ''VideoGame/TheLegendOfZeldaALinkToThePast'' was the result of palette limitations of the Super Nintendo.
** The Fishing Hole in ''[[VideoGame/TheLegendOfZeldaOcarinaOfTime Ocarina of Time]]'' [[http://iwataasks.nintendo.com/interviews/#/3ds/zelda-ocarina-of-time/2/3 originally came from someone goofing off while coding the Water Temple, making a fish in an isolated room and trying out a coded fishing rod.]] It was later put in to the actual game as a sidequest and even got a massive expansion in the UsefulNotes/Nintendo3DS remake of ''[[VideoGame/TheLegendOfZeldaMajorasMask Majora's Mask]]''.
** Ordon Village was developed for the [[UsefulNotes/ElectronicEntertainmentExpo E3 2006]] demo of ''VideoGame/TheLegendOfZeldaTwilightPrincess'' and wasn't originally meant to be in the actual game, but Creator/ShigeruMiyamoto [[http://iwataasks.nintendo.com/interviews/#/wii/twilight_princess/0/1 felt it would work well as a prologue section to introduce the game's mechanics]] and told the team to include it.
** ''VideoGame/TheLegendOfZeldaTwilightPrincess'' also had Green Chu Jelly, which was planned to replenish a magic meter that never made it into the final game, which ''could'' still be obtained in the Wii version by letting a yellow and blue chu merge in the Cave of Ordeals -- it had no text, and did nothing when drank. This was removed from the Gamecube version (yellow and blue chus make a purple chu in this version), but its existence became popular enough trivia among fans that the HD Remake made Green Chu Jelly available again via the same trick as the Wii version... as a [[UselessItem gag item]] with a description remarking how "it doesn't look all that tasty..."
* ''VideoGame/{{Bulletstorm}}'' is best known for having an [[ClusterFBomb oversaturation of swear words]]. This wasn't intentional by any stretch; because the swearing was in English and the developers of the game were Polish, they believed were using more mild, muttering swears like "damn" or "crap". Seeing as how one half of the game is about making insulting, violent kills, this plethora of insulting, violent swearing ends up as the other half of the game. The devs were reportedly horrified when the dialogue was translated back into Polish.
* The gauges screen in ''B-17 Bomber'' was originally meant to be a debugging tool to be removed in the final product but ultimately was left in because developers liked it so much.
* [[http://www.lostlevels.org/200407/200407-earthbound2.shtml The running feature]] in the English version of ''VideoGame/EarthBoundBeginnings'' was originally added in for debugging purposes (hence why it simply doubles the game's overworld speed), but localization director and English script writer Phil Sandhop convinced the development team to leave it in the final game due to how slow and plodding the game felt otherwise. A more conventional run feature, which only affects the player's overworld speed, was included in both the ''MOTHER 1'' half of ''[[CompilationRerelease MOTHER 1+2]]'' and ''VideoGame/{{MOTHER 3}}''.

** Reimu Hakurei, the iconic {{Miko}} heroine of the series, is an {{expy}} of Sayo/Pocky from ''VideoGame/PockyAndRocky'', but ZUN admitted in the manual for ''Embodiment of Scarlet Devil'' that he hadn't intended for her to stay that way -- the popularity of Touhou as "the shrine maiden shooter series" convinced him otherwise.
** In interviews, ZUN has also [[AscendedFanon paid lip service to fanon ideas]], such as the {{Fan Nickname}}s for Daiyousei and Koakuma, elevating them to canon status. Still other fanon ideas have shown up in the official spinoff manga, making them WordOfDante.
** In ''Undefined Fantastic Object'', [[https://www.youtube.com/watch?v=ofuPQIPotn0 Minamitsu Murasa's stage theme]] contains a sudden pop, caused by a Windows notification while ZUN was recording it.

** ''VideoGame/SonicTheFighters'' exists because a bored programmer at Sega [=AM2=] snuck Sonic and Tails into ''VideoGame/FightingVipers'' as playable characters.[[note]]The final version doesn't have them.[[/note]] Yu Suzuki found the gag amusing. He then showed it to Yuji Naka, who also loved it, and a collaboration was born. Consequently, ''Sonic the Fighters'' runs on a modified version of the ''Fighting Vipers'' engine. The same programmer threw in a FunnyAnimal version of Honey from ''Fighting Vipers'', who was DummiedOut in the original arcade release. For the HD re-release, they put the finishing touches on her and threw her in as a hidden fighter.

* Y'know [[https://www.youtube.com/watch?v=-MZdrJZo_ig the innuendos Dante says]] when he acquires Lucifer in ''VideoGame/DevilMayCry4''? Creator/ReubenLangdon apparently improvised them.

** Tiny Tina features a lazy eye that supposedly was a result of an animation glitch that the developers decided to keep. It definitely helps sell the maniacal CreepyChild vibe.
** According to WordOfGod, Handsome Jack's line about his pretzels, just before he speaks about his diamond horse Butt Stallion, was wholly improvised by his voice actor Creator/DameonClarke. Lead Writer Anthony Burch jokes that he's somewhat jealous that Jack's most famous line was something he did not write.

* Simon Viklund, music composer for ''VideoGame/PAYDAYTheHeist'', has several pieces of party music that he composed during his spare time. One of the levels in the game has a party going on and the game needed music for the event during the heist. Simon saw he had leftover music lying around and threw them in.
* The mouselook feature in ''VideoGame/DukeNukem3D'' was originally just something you could do in the map editor to help in building them. The developers thought that it would make for a useful gameplay feature as well, and decided to implement it thus. It became a cornerstone of modern FirstPersonShooter controls.
* The intro sequence for the FinalBoss of ''[[Website/GaiaOnline zOMG!]]'' included a random player character scripted shouting "Look out! It's huge!" Enough players actually responded with "ThatsWhatSheSaid" that the developers eventually added it as another scripted line.
* The infamous "bucket trick" in ''VideoGame/TheElderScrollsVSkyrim'', in which you can rob people without consequence so long as [[FailedASpotCheck you put a bucket or pot on their head]]. The developers discovered this trick a few days before the game was released, but decided not to patch it out because they thought it was funny. The developers have gone on record saying that they'll intentionally leave bugs in the game as long as they don't [[GameBreakingBug break the game]] or make it less fun to play (such as the bug that caused chickens to report crimes they witness the player committing, which, while incredibly funny, would not be fun to deal with for players who aren't aware of it).
* ''Videogame/GoatSimulator'' is '''built''' around this trope: any bug that didn't [[GameBreaking crash the game]] was deliberately kept in for your own amusement. And then they went back and [[RefugeInAudacity made an achievement for crashing the game anyway]].
* ''VideoGame/{{Nier}}'' has "boar drifting." You can ride around some of the giant (''giant'') boars, and a bug made it possible to drift at high speeds like a car. When it was discovered the makers decided it was hilarious and left it in. Many players agreed with the decision.
* ''[[VideoGame/TheLastOfUs The Last of Us: Left Behind]]'': This improvised line by the voice actress.

* The setting of the ''Franchise/DragonAge'' series gets its name from this; in development notes and forums, the continent that the game took place in was called The Dragon Age Setting, but it was often abbreviated to [[FunWithAcronyms TheDAS]]. Eventually the producers stuck with this and officially named the continent Thedas.
* Danny Skurge's sudden coughing fit in ''VideoGame/LimboOfTheLost'' sounds rather genuine; considering the poor quality of the voice acting otherwise, it is almost certainly a case of this.
* ''VideoGame/HomeworldCataclysm'' adds late in the game [[http://shipyards.relicnews.com/bentusi/super_acolyte.htm Bentusi Super Acolytes]]'' borrowed from a simple cheat/mod of the original game: adding capital-ship lasers to fighters by editing a ship's data file.
* The ''ending'' of ''VideoGame/{{Journey|2012}}'' arose from a glitch making it seem like the game had finished [[spoiler:after you die in the storm]] during one playtester's test. The playtester was apparently moved to tears by how profoundly moving it was, and as a result thatgamecompany went almost a year and a half over budget and into bankruptcy just to achieve that satisfactory ending.
* In ''VideoGame/YandereSimulator'', one of the "Easter eggs" is [[Manga/AttackOnTitan Titan Mode]], which turns everyone in the game but the PC into giants. The giants can be killed just as if they were normal sized, but due to the Unity engine's problems with ragdoll physics, the bodies would curl up into balls and then bounce around the map. The dev apparently enjoys these 'Titan meatballs' as much as the players, given that he's [[WordOfGod preemptively stated]] that he's not going to do anything about it.

* ''Franchise/MassEffect'': It is mentioned multiple times in the story and [[AllThereInTheManual Codex]] that all weapons are [[KineticWeaponsAreJustBetter mass drivers]]; lasers are only used as starship point defense, since their range is abysmal (and even worse in an atmosphere). Cutscenes, however, show Sovereign as using a giant, completely unrealistic laser as his main weapon. This was due to a lack of communications between the story and cinematics teams. However, the laser looked and sounded so awesome that no one could bear to get rid of it. Instead, it was retconned into molten ferrofluids fired at relativistic speeds (a weapon which the turians adapted as the Thanix cannon in ''VideoGame/MassEffect2'').

* During the development of ''VideoGame/Left4Dead2'' and seeing player behavior from ''VideoGame/Left4Dead'', the developers noticed how the players loved to make everything explode (using pipe bombs, shooting propane tanks and oxygen tanks). In response to this, the developers created the grenade launcher specifically for that purpose.
** The second game's level "The Sugar Mill" is infamous for containing much more Witches than any other level (most levels contain one or ''maybe'' two, but this one contains 7-8 ''at minimum''). While this was originally the result of a glitch, [[AscendedGlitch the developers ended up taking a liking to it]], and the outside lore for the game now includes the fact that Witches crave sugar due to their malnutrition but, to explain why there aren't as many Witches during the next level, they also have a heavy dislike for rain.
* The famous Nuketown map from ''VideoGame/CallOfDutyBlackOps'' started as an unofficial project by level designer Adam Hoggatt, who had a working design for it in just two days. The staff at Treyarch liked the map so much they decided to add it to the game.
* In ''VideoGame/DetroitBecomeHuman'', according to Connor's actor Brian Dechart, much of Connor and Hank's interactions were improvised despite the wishes of director David Cage.
* Oddjob in ''VideoGame/GoldenEye1997'' had an infamous case of HitboxDissonance. [[http://www.cracked.com/article_25867_one-gamingE28099s-oldest-arguments-was-just-settled-good.html This issue was known to the developers during testing, but they considered it so funny they left it in.]]
* In the very early ''VideoGame/{{Wipeout}}'' games, "Piranha" was somehow grossly mistranslated/misspelled as "Pirhana". The fluff decided to roll with it, explaining in the next games that the merger between the companies Pir and Hana had rebranded themselves Piranha between seasons. Indeed, ''Wipeout 2048'' - the latest release, but first chronologically - has the team racing as Pir-Hana.
* Fukua from ''VideoGame/{{Skullgirls}}'' was mostly designed as an April Fool's joke character to make fun of the MovesetClone trope in fighting games, and was partly to do a TakeThat against the infamous reveal of Decapre's addition to ''VideoGame/StreetFighterIV''[[labelnote:Context]]Capcom had acted like they were going to add an entirely new DLC fighter, speculation about possible fighters abounded in the ''Street Fighter'' community... and then Capcom destroyed all the hype by announcing "Cammy with a mask" as the [=SF=] community put it[[/labelnote]]. Massive positive response lead to Fukua being a permanent addition. Her name is also derived from a common misspelling of the protagonist Filia (U/I and K/L are right next to each other on most keyboards), which likely went on to influence her personality.

* While working on ''VideoGame/FalloutNewVegas'', Obsidian discovered that if you kill Orion Moreno as part of his fight but still get [[spoiler:the Enclave Remnants]] to fight for you, then in their BigDamnHeroes moment when they all drop out of the vertibird into battle, Orion's dead body will spawn as well due to the game still tagging him as part of the quest. J. E. Sawyer loved the idea, and theorized that his teammates were so pissed at his attitude that they went "no, you're coming on our last mission whether you like it or not", took his corpse with them, and dumped it out of the vertibird.
** Also in ''New Vegas'', Ambassador Dennis Crocker was meant to be Caucasian, as seen on his Collector's Edition card, but [[https://web.archive.org/web/20130327163252/http://www.formspring.me/JESawyer/q/239066969813297315 he was made African American after a recording mix-up led to the African American Emerson Brooks recording his lines]].

* ''VideoGame/BlazBlueChronophantasma'': During Bang's encounter with Litchi in his Arcade mode, he declares that for her 'I shall face the wrath of a thousand arrows, and gladly throw myself into a body of sethir. You need but ask!'. At least, that's the on-screen text - his voice actor apparently got the free rein to deliver it as 'And gladly throw myself into a body of... something or other. Sethir!' Given the way Bang is, it works just as well.
* In ''VideoGame/FateGrandOrder'', Arash-e-kamangir is one of the Servants you can summon. During one of the official livestreams promoting the Agartha sub-singularity, Tsuruoka Satoshi (the voice of Arash, Gilles de Rais, Spartacus, and others) was a guest. The fans voted him to do the voice of Arash's Noble Phantasm. He did, and threw in the lengthy chant (which you only see the text of in the Camelot singularity) as well -- and he's done this multiple times, [[https://www.youtube.com/watch?v=5zZ7muOoKTY most notably in AX 2018]].

* When the heroine of ''VideoGame/Drakengard3'' was being conceived, the artist drew a flower in her eye (literally [[BodyHorror growing out of its socket]]) to give her a more feminine appearance. [[Creator/YokoTaro The director]] said 'okay', and wrote an entire plot around what the flower was and why it was there.
* ''VideoGame/WolfQuest Anniversary Edition:'' Eagles are programed to [[ArtificialAtmosphericActions fly away with fish]] snatched from rivers. For some reason, they were able to glitch and drop fish even though this was never intended. The team decided to make this into a feature, and now the [[EasterEgg player can carry and eat said fish]]. It doesn't fill your wolf up very much though; it has less food value than a snowshoe hare, the second smallest prey in the game.
* ''VideoGame/RedDeadRedemption2'': At the beginning of "Polite Society, Valentine Style" in Chapter 2, during the ride to Valentine, while Mary-Beth, Tilly, and Karen sing a joke song about meeting "a friend in Valentine/Strawberry/etc.", at one point Karen mixes up the lyric, and the others chide her for screwing up before they all laugh about it. This was a genuine moment made during the recording that was left in the final game.

* Gonzalo Martin, who voices the main character in ''VideoGame/LifeIsStrange2'', is a native Spanish speaker so the voice director allowed him to improvise any lines in Spanish his character speak in order to make it sound more natural to anyone who is fluent in Spanish.
* Done InUniverse in ''VideoGame/AlienIsolation'' with the Working Joes which are effectively [[ShoddyKnockoff Target brand versions]] of the convincingly human-like androids produced by Weyland-Yutani or Hyperdine Systems. Since their creator Seegson lacks the technology and manufacturing capabilities to make a decent android these things live at the absolute bottom of the UncannyValley with bald rubber skin, glowing LED eyes, monotone robotic voices, laughably poor AI, and no facial movements. Seegson acts like this is intentional and markets them toward people who are prejudiced toward synthetics as these things "can't pass themselves off as real people" and they even use the tagline "You always know a Working Joe." Nobody's fooled:

* ''VideoGame/PowerBomberman'' originally had the Path of Glory stage and the Item Help area look the same, but when the former was given a visual revamp on version 0.7.5, the latter wasn't changed to match due to an oversight. The devs thought that having the old design be exclusive to the Item Help area looked nice, so they never changed it.
* ''VideoGame/RatchetAndClankGoingCommando'': After beating the final boss, you gain access to a first-person gameplay mode in the Specials menu. If you jump and throw the wrench in this mode, you'll bounce upwards a bit. If you do this next to a wall, the wrench immediately returns, allowing you to climb most walls in the game by spamming wrench throws. According to an interview, this glitch was actually discovered by Creator/InsomniacGames during the game's development, but since you can't do it until you beat the game, they decided to leave it in as a sort of EarnYourFun secret; ''VideoGame/RatchetAndClankUpYourArsenal'', which has first-person view available from the start, does not have this glitch.

* From ''Franchise/MortalKombat'':
** While the creators of ''VideoGame/MortalKombat1992'' were already well-prepared for the video shoots to create their digitized sprites and knew what they'd be shooting, they would also come up with ideas during the shoot that would then be filmed and added to the game. To take just the most notable example, Scorpion's iconic [[SignatureMove spear attack]] [[https://twitter.com/noobde/status/1447966875523162121 originated]] as a "cool-ass move" that Creator/EdBoon came up with on the spot while the ninja characters' sprites were being filmed.
** Reptile was added to the first game and became a mainstay in the franchise entirely because of some surreptitious mischief from series co-creator Ed Boon: when the game was released to [[SleeperHit surprise success]], Boon made note of the success of the PaletteSwap method of characters for Scorpion and Sub-Zero, and he decided one day to sneak in a third ninja as a SecretCharacter (more specifically "a cooler version of Scorpion"), finishing the code and visuals that same night and shipping him out for the third arcade revision of the game. This green ninja's inclusion was so quiet that no one else knew about his existence until he was already out in arcades, something that peeved co-designer John Tobias, leading the development of ''VideoGame/MortalKombatII'' to be more stringent on everyone in the development team being aware of any hidden characters...
** ...[[TheGadfly which still resulted in Boon doing the exact same stunt]]. While the entire team of ''II'' was aware of two other secret characters -- Smoke and Jade -- Boon secretly added another, all-black ninja named Noob Saibot, [[SdrawkcabName whose name was Boon and Tobias' spelled backwards]] as a cheeky nod to the previous scuffle. No one in the development team other than Boon was aware of Noob Saibot's existence until midway during development of ''VideoGame/MortalKombat3''.

* The narration of ''VideoGame/BattleBlockTheater'' contains a ''lot'' of misreads and lines where the narrator clearly accidentally stumbled, got tongue-tied, blurted out the wrong word, or [[CurseCutShort cut himself short of swearing]]. They were all left in as these perfectly fit both the tone of the game and the comedic style of the narrator Will Stamper. So much so that the [[https://www.youtube.com/watch?v=fIUE3aP1TFw two]] [[https://www.youtube.com/watch?v=9NJaTMgwi4A trailers]] wholly embraced Stamper's gaffes and basically just let him run wild.
--> I hope you're down because things are about to get... Platform/{{Steam}}y... in here-- that was weird, sorry, should have said, let's just see, let's just say Behemoth is about to release some steam! Oh man that was way better (footsteps stomping away) GOD!!!
* In ''VideoGame/AssassinsCreedOrigins'', protagonist Bayek starts off with long hair and a beard. After a few missions, you reunite with your wife, who cuts them for you. Players using a controller managed to find that pressing certain button combinations on the gear screen would make your hair and beard alternate between long and short. This was later confirmed to be a developer function that was accidentally left in. Since some fans liked mixing the long and short styles together, later updates added a visible hair and beard toggle to the gear screen, and some promotional screenshots for upcoming expansions had Bayek with mixed styles. This is likely what led to ''VideoGame/AssassinsCreedValhalla'' having multiple different hair and beard styles.
* In ''VideoGame/XenobladeChronicles1'', [[PluckyComicRelief Riki]] was originally going to have the lowest HP of the party, to match how he's a Nopon (small fuzzy mascot species). According to the Monado Archives, he was given the highest HP for a bit as a joke. Everyone liked it so much that it stuck, to the point where ''VideoGame/XenobladeChronicles2'''s main sponge tank character is a Nopon.
* ''VideoGame/StarTrekOnline'': The minor Klingon character B'Eler was reportedly scripted as male, but a miscommunication led to her getting a female character model while talking about having a female mate. The playerbase approved of the accidental lesbian Klingon and Cryptic later brought her back for "House Pegh", this time with aforementioned mate also present to make a BattleCouple.

** On the subject of Kefka: "[[SugarWiki/AwesomeMusic Dancing Mad]]", Kefka's final boss theme for which LaughingMad was named. Not so much that the song wasn't meant to be, but ''how much there ended up being of it'', was a complete throw-in by Uematsu, as revealed here:

*** Kefka's infamous introduction scene (barring the flashback) was not in the original script. Originally, he was intended to simply arrive at Figaro Castle and demand for Terra. However, Yoshinori Kitase felt that the scene was too boring to make completely normal, especially when they had only Amano's artwork of Kefka to work with, so he added in a scene where Kefka is complaining about Gestahl sending him off to Figaro, in the desert, on a reconnaissance mission, and then stating that there is sand on his boots, causing the soldiers to wipe the sand off, and then, after {{laughing ma|d}}niacally, berates them as idiots, with the intention of giving the implication that Kefka may be missing a screw or two from his head. They kept it in, and this also resulted in Kefka's characterization that we know him by to this day. On the subject of Kefka: "[[SugarWiki/AwesomeMusic Dancing Mad]]", Kefka's final boss theme for which LaughingMad was named. Not so much that the song wasn't meant to be, but ''how much there ended up being of it'', was a complete throw-in by Uematsu, as revealed here:

** Most of Kefka's dialogue in ''VideoGame/DissidiaFinalFantasy'' was actually ad-libbed by his Japanese voice actor, Creator/ShigeruChiba, and his tendency to change the tone of his voice mid-sentence was also due to Chiba.

** One of the mounts players can earn in PVP is the ADS mount, which is a giant metallic sphere. The idea came from a fan during a fanfest and the developers found it so hilarious that they threw it in.
** The Paladin's Passage of Arms skill in has the player kneel down and emit a huge pair of magical wings to protect the party from incoming damage. The animation came about from a developer who was messing around during the animation process. The other developers saw it and loved how cool it looked, causing them to keep it in the game.

* ''VideoGame/FinalFantasyXIV'':

* While the creators of ''VideoGame/MortalKombat1992'' were already well-prepared for the video shoots to create their digitized sprites and knew what they'd be shooting, they would also come up with ideas during the shoot that would then be filmed and added to the game. To take just the most notable example, Scorpion's iconic [[SignatureMove spear attack]] [[https://twitter.com/noobde/status/1447966875523162121 originated]] as a "cool-ass move" that Creator/EdBoon came up with on the spot while the ninja characters' sprites were being filmed.

* In ''VideoGame/XenobladeChronicles1'', [[PluckyComicRelief Riki]] was originally going to have the lowest HP of the party, to match how he's a Nopon (small fuzzy mascot species). According to the Monado Archives, he was given the highest HP for a bit as a joke. Everyone liked it so much that it stuck, to the point where ''VideoGame/XenobladeChronicles2'''s main sponge tank character is a Nopon.

----

--> I hope you're down because things are about to get... UsefulNotes/{{Steam}}y... in here-- that was weird, sorry, should have said, let's just see, let's just say Behemoth is about to release some steam! Oh man that was way better (footsteps stomping away) GOD!!!