History GoneHorriblyRight / AnimeAndManga

Times where a plan [[GoneHorriblyRight Goes Horribly Right]] in {{Anime}} and {{Manga}}.

* In ''VisualNovel/DaCapo'', the Giant Sakura Tree was intended to look after Sakura after her grandmother's death and use its magic to [[BeCarefulWhatYouWishFor fulfill all her wishes.]] Unfortunately, Sakura grows up to be a [[ClingyJealousGirl clingy jealous]] {{Yandere}} on the losing end of a love triangle [[MurderTheHypotenuse and the tree grants subconscious wishes.]]
** This is only in the anime. In the original VisualNovel Sakura is doing it unconsciously [[RealityWarper herself]].
* In ''Anime/Danganronpa3'', Ryouta's plans to [[spoiler: create an anime full of hope that includes brainwashing methods ended up working perfectly bringing [[BigBad Junko]] [[HopeCrusher Enoshima]] to tears. However, she used that anime to her benefit by brainwashing Class 77-B and Chisa to be members of the Ultimate Despair.]]
* ''Manga/DemonSlayerKimetsuNoYaiba'': This is what led to [[spoiler: the rise of Muzan Kibutsuji and the demons. Muzan was born a sickly boy who wasn't supposed to live up to the age of 20. Yet a doctor was able to cure him with an experimental medicine...except it turned him into a demon. The rest is history]].

* ''Manga/FairyTail''

** In Part Four: ''[[Manga/JoJosBizarreAdventureDiamondIsUnbreakable Diamond is Unbreakable]]'', Josuke is fighting Rohan Kishibe whose powers require his victim to look at one of his drawings to work. Josuke gets around this by keeping his eyes closed, even when stabbed by sharp objects. Rohan intentionally pushes Josuke's BerserkButton by insulting his hair, hoping to get him to open his eyes in anger. Josuke opens his eyes, but he gets so angry he becomes literally blind with rage, ignoring the drawing entirely and brutally pummels Rohan.
** At the end of Part One: ''[[Manga/JoJosBizarreAdventurePhantomBlood Phantom Blood]]'', [[spoiler: [[BigBad Dio Brando]] fatally wounds Jonathan Joestar; but before Jonathan dies, [[HeroicSacrifice he saves everyone from Dio]] [[TooGoodForThisSinfulEarth by simply holding Dio's head]],and GoesOutWithASmile; and when Dio tried to give a DealWithTheDevil with Jonathan [[YouAreTooLate it was too late, Jonathan was dead]], and [[Manga/JoJosBizarreAdventureStardustCrusaders it would take a long time before DIO becomes a threat again]].]]

* In ''Anime/YuGiOh'', Gozaburo Kaiba adopts an orphan named [[Characters/YuGiOhSetoKaiba Seto Kaiba]] to be the heir to his corporation, and puts him through TrainingFromHell to make him as ruthless as possible. A few years later, Seto Kaiba ousts his adoptive father and takes control of [=KaibaCorp=]. Interestingly, Gozaburo played this one [[Franchise/StarWars Palpatine]]-style: Seto succeeded because he'd earned it, and Gozaburo, as the loser, [[DrivenToSuicide had to pay the price]].[[labelnote:*]]In the dub, he [[NeverSayDie ran away and disappeared forever]] -- or at least until season 3.[[/labelnote]]
* In ''Anime/YuGiOhZEXAL'', III is the meekest of the Tron family, possibly qualifying as a MinionWithAnFInEvil. Once he decides that he needs to defeat Yuma to become a strong duelist, he asks Tron for power taken from Haruto in order to give him the confidence he needs. He gets far more than he bargained for; the dark spell turns him into an AxCrazy and sadistic sociopath that almost kills both Yuma and Astral in their worst battle to date.
* In ''[[Anime/YuGiOhARCV Yu-Gi-Oh! ARC-V]]'', the Professor takes advantage of Yuri's strength and trains him to be his most effective ChildSoldier, while encouraging him to enjoy his work. Yuri ends up being one of the strongest villains in the series, but only because he enjoys hurting people. In fact, Yuri enjoys his work so much that he plans on [[OmnicidalManiac carding everyone in the world, until he is the only survivor.]] He later forgets his work to pursue his own interest in finding his dimensional counterparts, defeating them and absorbing them.

* In ''Anime/YuGiOh'', Gozaburo Kaiba adopts an orphan named Seto to be the heir to his corporation, and puts him through TrainingFromHell to make him as ruthless as possible. A few years later, Seto Kaiba ousts his adoptive father and takes control of [=KaibaCorp=]. Interestingly, Gozaburo played this one [[Franchise/StarWars Palpatine]]-style: Seto succeeded because he'd earned it, and Gozaburo, as the loser, [[DrivenToSuicide had to pay the price]].[[labelnote:*]]In the dub, he [[NeverSayDie ran away and disappeared forever]] -- or at least until season 3.[[/labelnote]]

** Congratulations, Itachi. Your attempts to turn your little brother into a nigh-invincible, revenge-bent OneManArmy worked. Too bad people like that aren't interested in returning home a hero to live peacefully surrounded by friends like you wanted.
** Jiraiya teaching ninjutsu to three Hidden Rain orphans so that they could protect themselves turned out much better than he would have liked or expected. In his defense, it was not '''his''' actions and mistakes that turned them against Konoha. The blame goes right to Danzo's attempt to kill them GoneHorriblyWrong.

* A bonus story in the fifth volume of ''Manga/The100GirlfriendsWhoReallyReallyReallyReallyReallyLoveYou'' reveals that this is how Iku's masochism started. As a little girl, she was a crybaby who always gave up if things got too difficult, until her older brother gave her an encouraging pep talk about how one should always keep trying no matter how painful it gets. While it ''did'' encourage Iku to keep trying no matter what, it also caused her to consider pain a good thing.

** In ''Anime/DigimonAdventure02'', when [[GiantSpider Arukenimon]] created [[BetaTestBaddie BlackWarGreymon]] from a massive number of Control Spires, she probably didn't expect him to go insane from reflection over [[CloneAngst the implications of his formation]]. It certainly didn't help matters that he was a [[PowerLevels Mega level]], and therefore significantly more powerful than anyone in the existing cast, including Arukenimon herself and her partner Mummymon, both of whom are only Ultimate level.
** The [[EldritchAbomination D-Reaper]] of ''Anime/DigimonTamers'' started out as a [[FromNobodyToNightmare harmless automatic utility program]] designed to delete any data that grows beyond its original parameters and becomes a threat to the integrity of the system. Eventually, it was subdued by the very programs it was built to delete, and was laid to dormancy in the Digital World's center, to eventually fester into a nihilistic cybernetic menace PoweredByAForsakenChild, which began wreaking havoc in both the Digital and Real Worlds. In this, it has a single purpose: follow its prime directive to the letter by deleting anything that grows too much. Unfortunately, by that point, that directive means "[[OmnicidalManiac delete everything]]".

-->'''White Blood Cells:''' To think this all happened because everyone did their job properly...

** In ''Anime/DigimonAdventure02'', when [[GiantSpider Arukenimon]] created [[BetaTestBaddie BlackWarGreymon]] from a massive number of Control Spires, she probably didn't expect him to go insane from reflection over [[CloningBlues the implications of his formation]]. It certainly didn't help matters that he was a [[PowerLevels Mega level]], and therefore significantly more powerful than anyone in the existing cast, including Arukenimon herself and her partner Mummymon, both of whom are only Ultimate level.

* The scientists in ''Anime/PokemonTheFirstMovie'' create Mewtwo, who is not entirely happy with [[CloningBlues the circumstances of his "birth".]] He is also [[PhysicalGod extremely powerful]]. This... [[StuffBlowingUp doesn't work out too well.]]

* In ''Manga/UruseiYatsura'', the Mizunokoji family keeps its female heirs secluded from all male contact until the day of their ArrangedMarriage to ensure their purity. Unfortunately, the current heiress, Asuka, was attended to by extremely incompetent [[BodygurdBabes female protectors]], leaving her with little understanding and a considerable fear of men -- something only made worse by her first sight of a man being super-lech Ataru Moroboshi. To calm her fears, her attendants tried telling her about her big brother Tobimaro, and now he's the only man she's not terrified of... but because of her ignorance of male/female relationships, [[IncestantAdmirer she wants to]] ''[[IncestantAdmirer marry]]'' [[[[IncestantAdmirer her brother]].

** A RealLife example. Creator/AkiraToriyama has gone on record saying he disliked that the original ''Dragon Ball Z'' anime turned Goku into a more standard heroic protagonist rather than the self-centered and apathetic main character he was in the manga. Indeed, [[https://www.kanzenshuu.com/2015/03/27/new-interview-translations-akira-toriyama-special-talks/ as stated in an interview]] what he "wanted to depict the most was the sense that [Goku] might not be a good guy at all, although he does do good things as a result". ''Anime/DragonBallSuper'' attempted to follow this course by the virtue of being more faithful to the original source. The result that there's an awful lot of fans who believe that Goku is the main villain of ''Super'' due to his action during the "Tournament of Power" arc.

* ''LightNovel/RebuildWorld'': At one point when Akira is unable to access his home city and the FriendlyShopKeeper there he usually buys equipment from, the IntrepidMerchant Katsuragi comes to him with equipment he figures Akira can’t afford yet, [[TooDesperateToBePicky inflated to “the wasteland price”]], in order to try and get Akira into his debt and thus profit off of his IndenturedServitude. Katsuragi’s plan ends up as this when Akira spends [[ShockinglyExpensiveBill 18 billion aurum]] on the equipment which leaves Katsuragi collapsed in a fit of laughter.

* One of the ''LightNovel/{{Slayers}}'' OVA's features the shadow reflector, a MagicMirror designed to counter demons by creating [[EnemyWithout a copy of them loyal to the user with a completely opposite personality]]. It works, but since the opposite of an OmnicidalManiac is a person with [[ActualPacifist absolutely no will to fight]], the mirror is essentially useless and its creator hid it away in shame. The results when it gets turned against [[DestructiveSaviour our]] [[PersonOfMassDestruction heroes]] are highly amusing.

* ''Manga/{{Wagnaria}}'': Mahiru Inami's father trained her from birth to instinctively fear all men, so as to [[OverprotectiveDad protect her from any boy that tried to date her.]] Unfortunately, she decided that the best defense was a good offense, and instead ''attacks'' any man that gets within several meters of her, while yelling and crying from fear. Including her father.

* [[MagnificentBastard Sosuke Aizen]], of ''{{Manga/Bleach}}'', set in motion a 100 year long plan to become a PhysicalGod. In order to test his new powers against a WorthyOpponent, he set in motion a plan to have [[TheHero Ichigo Kurosaki]] become one as well. [[spoiler:Aizen became absurdly powerful, but he never transcended the limits of Soul Reapers and Hollows. Ichigo however, did, leaving Aizen no match for him.]]

** In [[Manga/JoJosBizarreAdventureDiamondIsUnbreakable Part Four: Diamond is Unbreakable]], Josuke is fighting Rohan Kishibe who's powers require his victim to look at one of his drawings to work. Josuke gets around this by keeping his eyes closed, even when stabbed by sharp objects. Rohan intentionally pushes Josuke's BerserkButton by insulting his hair, hoping to get him to open his eyes in anger. Josuke opens his eyes, but he gets so angry he becomes literally blind with rage, ignoring the drawing entirely and brutally pummels Rohan.
** At the end of [[Manga/JoJosBizarreAdventurePhantomBlood Part One: Phantom Blood]], [[spoiler: [[BigBad Dio Brando]] fatally wounds Jonathan Joestar but before Jonathan dies [[HeroicSacrifice he saves everyone from Dio]] [[TooGoodForThisSinfulEarth by simply holding Dio's head]], Jonathan Joestar GoesOutWithASmile and when Dio tried to give a DealWithTheDevil with Jonathan [[YouAreTooLate it was too late, Jonathan is dead]] and [[Manga/JoJosBizarreAdventureStardustCrusaders it would take a long time before DIO becomes a threat again]].]]

** Occurs to Trafalgar Law during the Pirate Alliance arc. He teamed up with the Straw Hats since he has faith in Luffy's ability as a [[spoiler: fellow]] D to wreak havoc and wants that havoc on his side, at least, since the Straw Hats are already there. He got ''way'' more than he bargained for and found himself constantly stunned by the Straw Hats' antics. Thankfully, the trope worked out in the end as Law really was right about Luffy...he just had to endure their sanity-destroying quirks for a while because of it.

* ''Webcomic/OnePunchMan'': Saitama wanted to become the hero who could destroy anything in one punch as a child. When he finally becomes that he gets bored of it because there's no challenge in his life.

* ''Shiori Experience'' has the protagonist band stuck in a rut after a disastrous performance and [[spoiler:their club president being so demoralized that she decides to quit the band, since she felt like she had no place as a sax player in a rock group]]. To win them over and make efforts to improve themselves, they take time off to perfect their instruments and pump their in-progress song with so much passion that they hope will get their message out. In the end, they ''did'' improve immensely, and they ''were'' able to make their feelings known--but they only proved the president right, in that [[spoiler:the song no longer has room for a saxophone part. And she only came back to resign.]]

-->'''Shadow Mei''': ''(angrily marching away with [[BindleStick her things wrapped up in a cloth on her back]])'' Humans... Matsuri Kazamaki... I will never forgive either.
* A minor one, but in ''Manga/{{Berserk}}'' Guts constantly seeks purpose in life. This eventually leads him to helping Grifith reach his dream, only to realize that once that's fulfilled Guts will not have a purpose anymore. This leads him to leave the Band of the Hawk which then sets in motion the series of events that give Guts a purpose at last: [[spoiler: getting revenge]].
* Researchers in ''Manga/{{BioMeat|Nectar}}'' created the eponymous [=BMs=]. They can and do eat anything except for glass, metal, and fiberglass (and apparently stone), to serve as living waste recyclers. They also are tough enough to ''chew'' through anything short of these materials. They are supposed to be an ultra cheap food source, and so they can multiply extremely rapidly, as long as there is enough food for them. And did we mention that they eat ''anything''? And when some of them get out of containment, horror ensues.