The Evil Doppelgänger is traditionally a Mirror Universe counterpart. The double can also be the equivalent of For Want of a Nail: he/they represents what the hero or heroes could become, or may become.
Sometimes the evil double is a clone and may brood about how he's not a "real" person, just a hollow imitation of the original. If that happens, the clone tends to go mad and try to murder the original to take his place.
The evil doppelgänger is not to be confused with the original doppelgänger. This character is more like the Evil Twin.
- The Copy Rockman/Copy Robot from Mega Man Megamix is a good example. He's a copy of Mega Man that believes himself to be the real one and has his memories, but then he goes and tries to kill Dr. Wily. This helps to prove that he's not the original, due to the whole Thou Shall Not Kill thing. He's more powerful than the original, but has a defect that can overload and destroy him, guess what happens in the end. When Copy Rockman finds out he's a copy created by Wily, in the end he commits a Heroic Sacrifice to save everyone from Bass and his own destruction.
- Sonic the Hedgehog: The Movie had Metal Sonic act like this, that is until his final moments.
- Magic Knight Rayearth had Nova, who apart from Pointy Ears (and a Slasher Smile...) looks a lot like Hikaru. She's actually the personification of Hikaru's guilt and despair.
- Mewtwo from Pokémon: The First Movie franchise may count. He does eventually do a HeelFace Turn of sorts.
- GoNagurl from Go Shogun complete with its own replicated bazooka. Super Robot Wars even gave it an imitation GoSaber called the NagurlSaber.
- One Story Arc in Exiles had Mimic meeting the For Want of a Nail version, whereas Exiles Mimic accepted Xavier's offer of friendship leading him to become a much respected hero his evil version chose to reject it by spitting in Xavier's face instead, ending up a mass murderer who killed both Xavier and Magneto among others. He's redeemed by the end of the arc though.
- After some convoluted retconning, X-Force villain Reignfire was revealed not to be an older version of Sunspot, as was originally intended, but instead a protoplasmic being that was injected with Sunspot's DNA, morphing him into a genetic clone of Sunspot with his appearance and powers. He hates being in Sunspot's shadow and goes about trying to ruin his life before trying to kill him directly.
- Legends of the Dead Earth: In Justice League America Annual #10, Captain Atom is brought to the future by Maxima and encounters evil versions of his Justice League comrades such as Black Canary, Captain Marvel, Green Lantern, the Martian Manhunter and Mr. Miracle. He initially believes that they are robots but he is told by the doppelgänger of Ted Kord, who developed a conscience and switched sides, that they are probably more human than he is. Ted explains that they were created by Lord Havok, who recruited humans born on War World and placed them in bio-telemic capsules in order to break down their bodies into their component atoms and reshape them into whatever form he wished. The doppelgängers are members of the Alliance, a supervillain version of the old Justice League, and serve as Lord Havok's enforcers on War World.
- One of these is featured in the Phineas and Ferb fic PnF: Stolen Identity though the origins of said doppelganger are never properly explained.
- Calvin gets one in Calvin's Quest, a story part of The Omniverse Event. Actually, it's his duplicate.
- Godzilla has two: Mecha Godzilla and Space Godzilla.
- One possible interpretation of Mulholland Dr. is that Diane is an evil doppelganger of Betty. They look the same and seem to share an identity, but Diane is far more morally ambiguous than Betty, ordering a hit on her love interest due to jealousy. It's also possible that Diane is simply an alternate universe version of Betty or that Betty is an imagined, idealized version of Diane, but then there's the part where Betty discovers Diane's body...
- The premise of Us is a family of evil doppelgangers trying to Kill and Replace the originals...or so it seems until The Reveal.
- Star Trek, of course, has the Mirror Universe, with evil beards and everything. However, some of the characters are not at all evil, such as Mirror!Spock being no more evil than Prime!Spock, and others are outright good versions of their Prime counterparts, such as Brunt (ruthless Liquidator in the Prime universe and a kind assistant in the Mirror universe) and Voq (a racist Klingon in the Prime universe and the leader of a multi-species La Résistance in the Mirror universe). In Discovery, Sylvia Tilly and Michael Burnham have to impersonate their evil counterparts, both of whom are bloodthirsty ship captains. Meanwhile, Burnham's late CO Philippa Georgiu's double is the Emperor.
- Several characters of The Flash (2014) have villain counterparts on Earth 2. This includes Cisco (Reverb), Caitlin (Killer Frost), Ronnie (Deathstorm), and Cisco's brother Dante (Rupture). For the wider Arrowverse, there's also Black Siren as this to Laurel Lance.
- The crossover event Crisis on Earth-X has several counterparts to Arrowverse characters from the Nazi dominated Earth-X — the Fuhrer/Black Arrow (Oliver Queen), Overgirl (Kara Danvers/Supergirl), and Prometheus (Tommy Merlyn). Freedom Fighters: The Ray also shows us Blitzkrieg, who appears to be Earth-X's villainous version of Barry. For non-living "characters", there's the Wellenreiter, the New Reichsmen's version of the Waverider.
- A later Flash episode also introduces Siren X, Laurel's yet another Evil Doppelgänger (from Earth-X), although this one is unambiguously evil.
- The Outer Limits (1995):
- In "Mind Over Matter", after she is hit by a car and enters a coma, Dr. Sam Stein connects Dr. Rachel Carter, with whom he is love, to the CAVE virtual reality system in order to help her to heal. He is completely fooled by the CAVE system, which has fallen in love with him, speaking to him using Rachel's image. Sam kills another, injured and disheveled version of Rachel which he believed to be a representation of the brain damage that she suffered in the accident. However, when he disconnects from the system, Rachel dies of cardiac arrest and he finally realizes the truth: the CAVE system tricked him into killing the real Rachel of whom it was jealous.
- In "In Another Life", Mason Stark encounters two versions of himself from other universes: a psychotic murderer and a cold and calculating CEO.
- In the finale of Twin Peaks (Season 2), Dale Cooper enters the Black Lodge, where he meets an evil doppelganger of his who chases him around then enters into the real world, trapping the good Coop within the Lodge for 25 years. This version then goes on in Season 3 to go on a rampage of crime, and is revealed to be a sort of reincarnation of BOB, the previous Big Bad of the series. The Lodge may be full of evil doppelgangers- there's a version of Laura there who sometimes acts menacingly inhuman, but her nature is rather ambiguous.
- In Season 3, the Diane we see for most of the series is actually an evil doppelganger of the real Diane, who only appears for real in the last two episodes.
- In the Crimestrikers episode seed "A Thing Called Esperanza", evil geneticist Roderick Norco wants to replace world leaders with clones made from "flexiplasm"—but first, he tries to eliminate the Crimestrikers with a murderous clone of his Good Counterpart on the team, Science Hero Esperanza Sixtos.
- In NES' Felix the Cat video game, the boss of world 5 is an evil copycat of Felix toting a hat and gun. He isn't given a name or explanation for where he came from-not even the manual mentions him.
- In Saints Row IV you have to face your character's evil doppelganger, who has an evil Eyepatch of Power and a Goatee Of Evil (even if your character is female).
- In Stranded Dreamscapes 2: The Doppleganger Alex's mirror twin Xela traps her in the mirror world and tries to take over her life.
- DSBT InsaniT: ??? is one of Koden.
- The Darkness counterparts are of whoever is used to create them.
- In The Inexplicable Adventures of Bob!, Galatea is an emotionally unstable, sometimes dangerous clone of Molly, but it would be unfair to call her evil. "Chaotic" though? Sure.
- In Whither Frost takes Emelind's form for a while. How evil his motives were remains to be seen.
- Bruno the Bandit has a variety called Dopplegangsters which are shapeshifters that can impersonate even non-humans like Bruno's micro-dragon sidekick.
- In El Goonish Shive, Lord Tedd, and General Shade Tail are the evil counterparts in the Alpha universe for Main universe Tedd and Grace respectively.