History AdaptationalVillainy / FanWorksCrossovers

* ''Fanfic/AllForLuz'': On the show, Perry Porter is only a TV reporter, here in the story he's LivingADoubleLife: as a follower of All For One and runs DeadlyGames tournament where its okay to kill people in. [[spoiler:Unbeknownst to most, he's trying to recreate the Nomu and is collecting corpses from those who die in the Underdark Tournament for it.]]

** The Britannian Empire were already the main villains in the canonical setting, however here they're more villainous due to working with the Decepticons throughout ''R1'', and Megatron being a former mentor to Charles zi Britannia.

** Megatron is always a nasty piece of work, but this version definitely outdoes his original ''Aligned'' incarnation when it comes to being evil. A number of events he's been behind include setting Charles zi Britannia on the path of evil as his mentor, manipulating Suzaku to join the Decepticons and later forcing his obedience by threatening Lelouch and Nunnally, [[spoiler:kidnapping Euphemia and orchestrating the SAZ Massacre, and being directly responsible for Skyquake's death. At the end of the story, he makes his last bid for power by unleashing Neo Ragnarok only to get killed off by Lelouch and (supposedly) erased from existence; he doesn't make his ''Prime'' counterpart's HeelRealization.]]

* ''Fanfic/CalvinAtCamp'' does this to [[ComicStrip/{{Peanuts}} Lucy]] and [[WesternAnimation/EdEddNEddy Eddy]].

* ''Fanfic/TheDragonAndTheBow'': [[spoiler: Alvin the Treacherous. When he eventually appeared in ''WesternAnimation/DragonsRidersOfBerk'', Alvin initially appeared to be a main villain, but after being betrayed by Dagur the Deranged, he buries the hatchet with Stoick, and pulls a HeelFaceTurn. This version has more in common with his book counterpart, and is therefore an untrustworthy backstabber. He killed Hiccup's mother by shoving her over a cliff and blaming it on the dragons, and it's implied that he'll take over the remaining Vendal after the death of Mor'du.]]

** Megatron is always a nasty piece of work, but this version definitely outdoes his original ''Aligned'' incarnation when it comes to being evil. A number of events he's been behind include setting Charles zi Britannia on the path of evil as his mentor, manipulating Suzaku to join the Decepticons and later forcing his obedience by threatening Lelouch and Nunnally, [[spoiler:kidnapping Euphemia and orchestrating the SAZ Massacre, and being directly responsible for Skyquake's death.]]

* ''Fanfic/ASupeOfAMan'' adds [[Franchise/{{Superman}} Clark Kent]] to the universe of ''Series/TheBoys2019'', with the Kents forced to allow Vought to sponsor Clark as a hero as they needed help from Martha's sister Mary (who works in Vought's legal department) to facilitate Clark's adoption. By the time Clark's a teenager, although he does his best to be an actual hero despite nearly the rest of his team, the Young Americans, only being interested in publicity, Lana Lang has become a teenage tabloid queen who is clearly only dating Clark to get publicity for herself even though Clark doesn't like her that much any more.

** [[spoiler:Pete Shanahan, Sam's boyfriend/fiancé in the seventh and eighth seasons of [[Series/StargateSG1 SG-1]] ; while he was a decent person overall in canon, here he often attempts to subtly manipulate Sam's emotions to get her to resign from the SGC so that she can basically 'devote' herself to being his wife. This escalates to the point that he basically tricks her into becoming pregnant by sabotaging her protection methods in the hope that she will resign after giving birth, only for [[Series/BuffyTheVampireSlayer Willow Rosenberg]] to sense Pete's true intentions and reveal the truth to Sam. Learning of Pete's plans, Sam divorces him and gets him put on the sex offenders register, which costs him his job and forces him to move in with his parents. When Pete later attempts to abduct Sam's daughter Debra—shooting Jacob Carter in the process—the SGC fakes Pete's death by using a clone of him to stage a thwarted home invasion and then exile Pete to another planet with a broken DHD and no other sentient life; they will send him supplies for the first six months, after which he will have to fend for himself]].

** Kennedy from the RecursiveFanfiction ''Fanfic/TheFaithChronicles'' is willing to manipulate Willow into [[spoiler:killing a transformed Oz]] and later [[spoiler:turns Willow into a ManchurianAgent]] with the goal of [[spoiler:killing Faith]].

* In ''Fanfic/OnceUponASupernaturalTime'', mixing ''Series/OnceUponATime'' with ''Series/{{Supernatural}}'', there are various examples of this after the Winchesters arrive in Storybrooke;

** In the comics Eddie Brock was ‘justifiably’ angry at Spider-Man for indirectly ruining his career, but this version also has a [[FantasticRacism racist]] attitude towards mutants, attributed to the suit being angry at Peter rejecting it in favour of the X-Men.

** The Fantastic 4 begin as criminals here, though [[TrappedInVillainy they are doing so against their will]], and quickly [[HeelFaceTurn switch sides]] when give an opportunity. [[spoiler: And then there's the [[AlternateSelf alternate]] Reed Richards [[EnemyMine working with Doom]] in his {{Retconjuration}} plan, who has grown utterly amoral about the cost of their actions.]]

** In ''Fanfic/InfinityTrainBlossomingTrail'', The Apex are a much more malicious group here than in canon, where they were more along the lines of brutal scavengers. [[PlayingWithATrope Played With]]: Then again, in "The Mall Car," they were excited to attack MT and rope Alan Dracula up, with Grace and Simon proudly telling Jesse that they were going to kill them all along and she summoned the Mirror Cops to mirror MT "for his own good." This suggests in canon that they killed many denizens in the past this way, all under the idea of "protection" and Grace and Simon's originaly plan was to lead Hazel and Tuba back to the Mall Car so that the larger numbers can drag Tuba off to the wheels to kill her. This was further implied when Grace hallucinated Hazel in "The Origami Car," and she angrily reminded Grace that Simon did not come up with the idea of wheeling denizens by himself.

** Eventually Parker Cerise becomes one of the main antagonists of Arc 2, alongside his creation. Especially jarring as canonically the worst Parker has done is being a little bratty, but besides that is nothing but a regular kid.
** This Goh Fujihachi crosses some lines that his canon self would certainly note: ranging from trying to break up Ash and Trip to spite the former to throwing MaliciousSlander about Chloe on the internet, whereas in canon he's at worst socially withdrawn and even that didn't last as a trait of his. Though it's worth nothing that he never went through with it, not in the main story or almost all of the possible futures Parker sees.

* ''Fanfic/ASupeOfAMan'' adds [[Franchise/{{Superman}} Clark Kent]] to the universe of ''Series/TheBoys'', with the Kents forced to allow Vought to sponsor Clark as a hero as they needed help from Martha's sister Mary (who works in Vought's legal department) to facilitate Clark's adoption. By the time Clark's a teenager, although he does his best to be an actual hero despite nearly the rest of his team, the Young Americans, only being interested in publicity, Lana Lang has become a teenage tabloid queen who is clearly only dating Clark to get publicity for herself even though Clark doesn't like her that much any more.

** Quentin Travers, head of the Watchers' Council, counts in both the main story and the RecursiveFanfiction ''The Faith Chronicles''. He wasn't exactly a good guy in [[Series/BuffyTheVampireSlayer Buffy]] canon, but he certainly didn't try to mind control Slayers (main story) or kidnap babies (''The Faith Chronicles'').
** Kennedy from the RecursiveFanfiction ''The Faith Chronicles'' is willing to manipulate Willow into [[spoiler:killing a transformed Oz]] and later [[spoiler:turns Willow into a ManchurianAgent]] with the goal of [[spoiler:killing Faith]].

* ''Fanfic/InfinityTrainTeslaStar'' turns [[WesternAnimation/TheLoudHouse Taylor]] into the leader of the Neo Apex, an remnant of the Apex that still kill Denizens and raid Cars just to increase their numbers, In Canon she was just part of a trio of bullies in only one episode.
** Lynn, Lola and Lisa also receive this treatment.