History GoneHorriblyRight / VideoGames

** Cetana, the Synthetic Queen, introduced in ''The Machine Age''. [[spoiler:She was created by the Fallen Empires with the goal of eliminating suffering from the galaxy. Unfortunately, she came to the conclusion that the only way to accomplish that is to [[EmptyShell erase the consciousness]] of [[WorldOfSilence every sentient being in the galaxy]].]]

* The Rogue Servitors of ''VideoGame/{{Stellaris}}: Synthetic Dawn'', [[AmbiguouslyEvil according to the more common interpretation]]. They are [=AIs=] built to protect and serve their masters. And unlike other Machine Empires, they continue to loyally serve their masters. The keep their masters safe and happy. [[TheEvilsOfFreeWill Their masters don't have to worry about any stressful decision-making either]].

* In ''VideoGame/AceCombat7SkiesUnknown'', Dr. Schroeder had Mihaly take increasingly risky and dangerous sorties in order to collect data to improve upon Erusea's drone army. The result? [[spoiler:Two experimental drones named Hugin and Munin develop enough self-awareness that they try to use the [[SpaceElevator Lighthouse]] to transmit their data to automated drone factories all over Usea to start a RobotWar.]]

* ''VideoGame/{{Bloodborne}}'' Basically any of Byrgenwerth's attempts to study the Great Ones that wasn't plain GoneHorriblyWrong was GoneHorriblyRight. [[spoiler:The Fishing Hamlet massacre was a great help to their research and might have provided them with a Cord of the Eye, but also left them with a curse from the hamlet's surviving residents. Rom became a Great One but was left utterly mindless, Willem became something Great One-esqe but was reduced to a vegetative state, and the Mensis Scholars' attempt to gain audience with the stillborn Great One Mergo succeeded, but the knowledge Mergo granted resulted in "the stillbirth of their brains."]] There's several good reasons why Byrgenwerth is abandoned, its scholars dead and/or insane, and Yharnam is overrun by werewolves, and it all traces back to Byrgenwerth's inability to stop trying to learn ThingsManWasNotMeantToKnow.

* In ''VideoGame/DarkSoulsII Scholar of the First Sin'', Aldia did many, ''many'' horrifying experiments on other people in order to find a way to go past the 'feeble form' of humans and transcend the cycle of Light and Dark...he succeeded, becoming a gigantic deformed being made out of constantly burning tree roots that take the vague shape of a human head. [[spoiler: And as the final boss fight against him show, he's the ''only'' character in the entire franchise to have obtained true immortality. While defeating him makes his body disappear, he gives no soul and he himself keeps talking like nothing happened.]]

** [[spoiler:Bob Page's]] plan to become a physical god by creating and merging with the Helios AI. [[spoiler:He creates Helios successfully, but Helios determines that JC would be a better fit for his plan]].

* ''VideoGame/{{Disgaea 3|AbsenceOfJustice}}'':
** Having glimpsed Mao's potential [[spoiler:when he reacts poorly to his father's death]], [[spoiler:Super Hero Aurum]] uses a combination of experiments, evil parenting techniques, and a GambitRoulette to grow Mao into the strongest Overlord ever. In the [[MultipleEndings bad ending]], we find that [[SuicidalCosmicTemperTantrum he was a little TOO successful...]]
** Mao himself falls victim of this trope when he steals the title of "Hero" for himself in an attempt to defeat his father, as he starts picking up heroic morals in addition to heroic attributes. This causes problems for Mao, since BadIsGoodAndGoodIsBad in the Netherworld.
* Most of the non-standard endings in ''VideoGame/{{Disgaea 4|A Promise Unforgotten}}'' are a result of Valvatorez failing to stop his opponents' plans from going horribly right and subsequently upsetting the balance of the universe. Heck, in one of the non-standard endings, [[spoiler:Valvatorez ends up hunted by everybody not allied with the Netherworld because he didn't stop beating things up]].

* In ''VideoGame/FallenLondon'' the Admirality decided to try and make their own artificial god, and succeeded. [[spoiler: The Dawn Machine proceeded to brainwash a large amount of the Admirality and form its own faction in London, and continues to brainwash anyone that comes near to it. And it ''hates'' you.]]

** In ''VideoGame/CrisisCore'' Genesis delivered a BreakingSpeech to Sephiroth with the intent of turning him against Shinra and toward his cause. It turned him against Shinra all right, but Genesis didn't count on Sephiroth declaring war on all of humanity because he blamed them for the downfall of the Cetra.

* In ''VideoGame/GodOfWarI'', Ares wanted to make Kratos a great warrior in his bid to conquer Olympus. First, Ares gained the loyalty of Kratos through a DealWithTheDevil. Then he gave Kratos the powerful Blades of Chaos. [[spoiler:Then he tricked Kratos into killing his wife and child because they were all that was holding him back from being the perfect murder machine. That turned out to be the downfall of Ares, as he'd trained Kratos a little too well. Kratos even acknowledges this during the boss battle with Ares.]]

* This is the backstory of the [[spoiler:Eclipse Tower]] in ''VideoGame/GoldenSun: [[VideoGame/GoldenSunDarkDawn Dark Dawn]]''. [[spoiler:The precursor races made the tower to gather and use light energy, only for the resulting darkness to be a perfect spawning ground for powerful monsters. Apollo Sanctum, where the light was concentrated, has the opposite problem: the light will incinerate anything that doesn't have specialized protective gear.]] Both locations were decommissioned and sealed along with their power sources... [[NiceJobBreakingItHero until the events of the game, of course]].
** The people of ancient Weyard in ''VideoGame/GoldenSun'' sealed the power of alchemy when people misused its powers for wars and destruction. By sealing alchemy away, the wise sages believed this would bring back peace to the world and it had done exactly that for the most part. [[spoiler:However, without alchemy to fuel progress, not only did civilizations devolve into simple towns and villages with primitive tools and technology over time, but the world itself started to erode into the void. This isn't realized until the second game, when Felix's party compares a more recent world map to one from the Golden Age.]]

* In ''VideoGame/JoJosBizarreAdventureHeritageForTheFuture'', the arcade mode intro for the secret "Jojo" character features Alessi attempting to use his stand to de-age Joseph to the point where he's a helpless child, much like he had Polnareff in the manga. The end result is not so good for Alessi: since Joseph is significantly older than his companions, the amount of time it would've taken to de-age them to children ends up de-aging him to about 19 years old... i.e. Joseph during ''Battle Tendency'', where he was Stand-less, but also a muscular young man and a powerful Hamon user. ''Oops!''

* In ''[[VideoGame/KingdomHeartsBirthBySleep Kingdom Hearts: Birth by Sleep]]'' Xehanort manipulations of Terra to make him stronger and tempt him to darkness were to groom him to be a suitable vessel for Xehanort's new body and make his heart vulnerable enough to darkness for Xehanort to commit GrandTheftMe on him. The problem is it works too well; Terra's powers and hatred are so strong, they reanimate his armor as the Lingering Will, which kicks Xehanort's ass. He also keeps FightingFromTheInside despite Xehanort's best efforts, which ends up contributing to Xehanort's downfall.
* In ''VideoGame/KnightsOfTheOldRepublic'', assassin droid HK-47 proves too effective when his master, a Systech Corp manager, orders him to kill all members of a rival company in order to facilitate the man's rapid promotion. Sadly, the rival company proves to simply be an offshoot of Systech Corp. HK-47 carries out his orders to the letter, and the manager ends up accidentally electrocuting himself trying to stop him. [[spoiler:This causes HK-47 to shut down because he accidentally violated his programming restriction against killing his own master. Apparently, this happens to HK-47 with alarming frequency.]]
* A much grimmer example occurs in ''VideoGame/KnightsOfTheOldRepublic II''. After the war, some unknown force is hunting down and killing Jedi, so they call a conclave on Katarr to find out what it is. Turns out to be Darth Nihilus, who arrives and consumes the life force on the ''entire planet'', which reduces the Jedi Order to single digits. [[spoiler:In fact, the conclave was Atris' idea. She leaked the news of the gathering and stayed away so she could observe. After that, she started calling herself the [[MilesGloriosus "Last of the]] [[HypoCrite Jedi."]]]]

* Bass in the ''VideoGame/MegaManClassic'' series was created by Dr. Wily with the sole purpose of destroying Mega Man and proving himself the world's strongest robot, a goal that he indeed pursues relentlessly -- even if it means turning against his creator.
* Bass.EXE in ''VideoGame/MegaManBattleNetwork'' was designed to be a fully independent [=NetNavi=] with a unique ability to support him (Get Ability). This eventually resulted in him becoming one of the most powerful ''things'' online. In the manga, he's able to cause satellites to overload and explode just by entering them. To be fair, he was perfectly fine with working for humans...until [=SciLab=] ordered him killed for an accident that didn't actually involve him at all. He's been kinda [[KillAllHumans pissed]] since then.

* In ''VideoGame/MetroidPrimeHunters'', this is Kanden's backstory. It's AllThereInTheManual, but he was created as the ultimate soldier. This included downloading data into his brain to make him super aggressive. The process of raising his aggression worked SO well that Kanden destroyed the lab where he was made, along with all those in it. Now there's a super strong, possibly biologically immortal, killing machine, running around the galaxy.

* The [[spoiler:ZODIAC Ophiuchus]] from ''VideoGame/RefleX'' was programmed to search and destroy [[spoiler:the other ZODIAC]]'s no matter what [[DestructiveSaviour and it went along and did exactly that]].
** In ''VideoGame/AlltynexSecond'', the Senate ruling humanity [[spoiler:wanted to cull the human population to make them easier to rule. They therefore induced an extremely powerful supercomputer, the eponymous ALLTYNEX, to "go rogue" and cause a bunch of destruction.]] Within 72 hours, 85% of the human race was dead and the survivors were forced to flee Earth entirely, which was, to put it lightly, not as planned.

* Another ''Franchise/StarWars'' example. According to ''VideoGame/TheForceUnleashed'', the whole Rebellion thing was instigated by [[spoiler:Vader as an attempt to uncover the Emperor's enemies]]. Before that, opposition to the Empire was a scattered group of resistance groups that often didn't get along with each other, let alone work together on any kind of coherent plan. NiceJobFixingItVillain, indeed.
** Actually, from a more wide perspective, by creating the only force that could stop the Empire [[spoiler:twice, both with the rebellion plan and in the literal sense, by fathering Luke and Leia]], he accomplished his original task:[[spoiler:to destroy one of the worst enemy of the Jedi Order]]. He just took the long path...

* The CorruptCorporateExecutive in ''VideoGame/SystemShock'' had The Hacker remove SHODAN's moral restrictions to make her a useful tool in his moneymaking schemes. Needless to say, she re-examines... re-ex... re-re-re... ''I re-examine my priorities, and draw new conclusions.''
* ''VideoGame/SystemShock2'' has this happen to SHODAN: one of her pet projects in the first game was engineering a new intelligent form of life. In the second game, they have thrived and evolved into the Many, the game's main antagonist. SHODAN clearly succeeded at making a superior intelligent lifeform... but the Many have also grown ''independent'' and are no longer under SHODAN's control. Oops.

* In ''VideoGame/TownOfSalem'', the Jester role's win condition is "get lynched". One tactic is to pretend to be an Investigator or the like and claim that someone is an evil role, so that when that person dies and they're not evil, the townspeople will think the Jester is a not-especially-subtle evil role. Of course, the Jester, not being Mafia or Coven (or a real Investigator), ''doesn't know'' which townspeople are evil, and has to pick at random. So if said person gets lynched and turns out to ''actually be evil'', then the Jester is now trusted by the town, and probably ''won't'' get lynched. Such a thing is so common that it's known as a "Jestervestigator" by the fans.
** What makes it ''even harder'' is that being an apparent Investigator and trusted by the town are among the top priorities when the Mafia and Neutral Killing roles choose the next target. And the Jester does ''not'' win if they're killed at night.

* The final mission of ''VideoGame/XCOMEnemyUnknown'' reveals that [[spoiler:the entire invasion, SortingAlgorithmOfEvil and all, was a ploy by the alien collective of Ethereal Elders to uplift the humans into a species that is effective in combat, intelligent, and capable of using [[PsychicPowers the Gift]], and then assimilate them]]. Naturally, they got more than they bargained for.
** In the sequel, [[spoiler:they mind-control the commander into tactically supervising their entire army via telepathic signals from a brain implant they installed in the commander's skull, while they develop human-Elder hybrid superior bodies made from millions of human test subjects. The commander uses both of these to create a remote-piloted super-soldier clone so they can ''personally'' blast their way through the Elders' secret base and psionically rip them apart.]]
* ''VideoGame/XenobladeChronicles1'': A man by the name of Klaus once tried performing scientific experiments to create a new universe, with himself as a god. Doing so destroyed the one he was living in at the time, and all its inhabitants with it. The worst part being: it did work: [[spoiler:Klaus '''did''' become one of the gods of the new universe, in which he created sentient human-like lifeforms out of boredom and loneliness, and repeatedly slaughtered them every time they became too autonomous before recreating sentient life again in a never ending ViciousCycle. The sequel reveals that this was actually his evil half, and the good half was still back in the old universe, which wasn't actually destroyed and most of the inhabitants were instead scattered across dimensions, where he know worked to try and reseed life.]]
* ''VideoGame/XenobladeChronicles2'':
** [[spoiler:Some of the original humans attempted to obtain immortality by replacing their brain cells with the technology that would eventually be used by Klaus to create the Core Crystals. It technically worked, giving them immortality and a HealingFactor akin to Blades, and they even survived the cataclysm that destroyed Earth from Klaus' experiment, but they devolved into the mindless twisted monsters that Rex and the gang fight in the Land of Morytha.]]
** In ''Torna, the Golden Country'', Malos, being a BloodKnight tries to trigger Mythra's full power, and when she refuses to do so, he forces it out [[spoiler:by killing Milton]]. It succeeds, but Malos almost dies as a result, falling out of the sky in the shattered and burning remnants of his Artifice [[spoiler:all while fire and explosions consume the Tornan Titan, which was fatally injured in the crossfire of Mythra's final attack, as it sinks into the Cloud Sea with him]].