With Marvel's mutant characters on their way to the MCU, many fans are looking back on the original film franchise that introduced them to general audiences. Fox's X-Men franchise is one of the longest superhero series in movie history, running over the course of 19 years, with 13 films including prequels and spinoffs, introducing dozens of fan-favorite mutants over this period of time.
Given the length of its run and the sheer number of characters therein, Fox's franchise was prone to occasionally reboot a character with little explanation as to how or why they would do such a thing. As such, there remain several unexplained duplicate mutants in this film series, about which fans still await answers.
Emma Frost
Fans of the X-Men franchise are certainly familiar with the mutant member of the Hellfire Club, Emma Frost, who possesses telepathic powers as well as the ability to turn her skin into near-unbreakable diamond. Played by Mad Men star January Jones, Frost appears in X-Men: First Class, but is killed off sometime in between that film's end and the beginning of Days of Future Past.
While many viewers may have taken Emma Frost to be a one-shot villain in X-Men: First Class, many be surprised to learn that this was actually not the first time she had appeared in the X-Men franchise. In fact, though never named through dialogue, there is a mutant in General Stryker's facility at the end of X-Men Origins: Wolverine that seems to have the exact same power set as Frost. A dive into the film's cast will reveal that this mutant, played by Tahyna MacManus, is indeed credited as Emma Frost.
Angel
One mutant that Fox has consistently and objectively failed is Warren Worthington III, otherwise known as Angel. The mutant is a part of the original X-Men lineup in the comics but doesn't make his first appearance until X-Men: The Last Stand, where he is portrayed by Ben Foster. The character then plays only a very minor role in the film's events, never to be seen again.
While Foster's Angel never again makes an appearance, the character himself does, albeit in name only. Ben Hardy portrays the winged mutant in X-Men: Apocalypse, but it is abundantly clear that this is not the same character seen in The Last Stand. This version of Angel is not only born several decades early but acts as an antagonist throughout the film, a far cry from the mutant introduced years earlier.
Jubilee
Jubilee has had a turbulent relationship with live-action portrayals, which began with a silent cameo in the original X-Men film. Katrina Florece appears in a classroom scene, sporting the signature style of the famous mutant, though she never gets any significant screen time thereafter.
Fans of Jubilee were delighted to learn that the character had landed a feature role in X-Men: Apocalypse, portrayed by Lana Condor. However, there were some timeline issues that failed to be addressed, making it impossible for Condor's character to be the same mutant seen in the original film. Regardless, Apocalypse failed to adequately portray Condor's character, causing fans to already start looking for the next actress to play the iconic mutant.
Quicksilver
Quicksilver, the speedster mutant that has appeared in both X-Men and MCU properties, actually makes his first appearance in a surprising cameo at the end of X-Men Origins: Wolverine. The mutant appears as one of General Stryker's prisoners but is not officially credited, though he is clearly modeled after the infamous X-Man,
Fans of the franchise know that Quicksilver made his first proper appearance in Days of Future Past, played by Evan Peters. The character would prove to be a hit among audiences, going on to appear in two more X-Men films before the end of the franchise. Evans would also appear as a fake version of the speedster in the MCU series WandaVision.
Psylocke
The character of Psylocke is perhaps better known to comics fans than moviegoers, due in part to her insultingly small role in Fox's live-action universe. Mei Melancon plays the mutant in X-Men: The Last Stand, who acts as one of Magneto's many forgettable henchmen, ultimately dying without making much of a mark on the film at all.
Olivia Munn would play a rebooted Psylocke in X-Men: Apocalypse, taking place nearly thirty years before Melancon's original portrayal. This version, though an improvement over that of The Last Stand, was similarly left behind by the screenwriting, perhaps requiring a third variant of the character to finally get her right.
Colossus
The mutant Colossus is an incredibly important part of X-Men lore, especially in the early days of their comic history. As such, the X-Man makes two appearances in the original X-Men franchise, appearing in a small role in both the second and third films of the series, portrayed by Daniel Kudemore.
It was the Deadpool franchise that would finally catapult Colossus into the limelight, while also making clear that this was a different version than the one seen in the original films. Deadpool's Colossus, apart from being played by Stefan Kapicic rather than Kudemore, has a completely different design, as well as an accent that the character didn't have previously, all of which indicate that the franchise has had not one, but two different Colossuses.
Caliban
Caliban is a relatively minor mutant in the comics, which perhaps s for his equally small role in his first live-action appearance. The character cameos in X-Men: Apocalypse, played by French actor Tómas Lemarquis, and is apparently killed off by the film's eponymous villain.
Caliban somehow returns decades later in Logan, this time portrayed by Stephen Merchant. This time, Caliban appears to be British, not French, and has a distinctly different personality than that of the character depicted in Apocalypse, indicating that, despite sharing a name, this is not the same version of the character as audiences had seen only two years earlier.
Sabretooth
Sabretooth is known as one of Magneto's first henchmen, appearing in the original X-Men film, where he was portrayed by the aptly named Tyler Mane. The character appears to die in the battle at the Statue of Liberty, and never appears in any installments of the franchise set in the years after this particular movie.
X-Men Origins: Wolverine, which is set years before the original film, seemingly introduced a second version of Sabretooth, played by Liev Schrieber. This version is revealed to be Wolverine's half-brother, with whom he fought alongside for decades. While this could technically still be the same character as Mane's version, the fact that the history between himself and Wolverine is never brought up in later installments implies that this is not the case.
Juggernaut
X-Men: The Last Stand is the first film in the franchise to introduce the fan-favorite X-Men comic villain, the Juggernaut. Played by Vinnie Jones, the character quickly became a laughingstock among the fandom, in part due to the poor adaptation of such an iconic character.
Deadpool 2 would see this character's return, albeit in a very different form. Voiced by Ryan Reynolds himself, the Juggernaut depicted in this film has a far different personality and is considerably larger than Jones's version, falling more in line with the character seen in the comics.
Deadpool
The infamous Merc With A Mouth has a spotty history with the X-Men franchise, beginning with the universally-hated X-Men Origins: Wolverine. In this film, Ryan Reynolds plays Wade Wilson for the first time, quickly disappointing fans as they realized that everything great about the character had been stripped away, including his signature witty dialogue.
In a stunning turnaround, however, Reynolds returned to play the murderous mutant in his own standalone franchise, beginning with 2015's Deadpool. This version is implied to be completely separate from that seen in Origins, though, given Deadpool's fourth-wall-breaking humor, this horribly misguided rendition of Wade Wilson is referenced often, remaining the only duplicate that the franchise has actively addressed.
