Fox’s X-Men franchise teased a wealth of characters who never materialized. However, the Marvel Cinematic Universe can finally fulfill them.

Fox’s X-Men universe set up several mutant introductions that went unfulfilled, which the Marvel Cinematic Universe can now finally actualize. The X-Men movie timeline was littered with thrilling Easter eggs and references to other characters from Marvel’s mutant pantheon. While many of these later appeared in some form, some were completely forgotten about, remaining as tantalizing teases for what could have been.

With the X-Men officially joining the MCU’s timeline, the franchise has the power to redeem some missed opportunities regarding character teases. The MCU’s Deadpool & Wolverine seems primed to address the presence of mutants in the franchise and the MCU’s future, meaning that many of these characters can finally be allowed to flourish.

10. Scarlet Witch Was Teased As Quicksilver’s Sister

Scarlet Witch Has Played A Key Role In The MCU

In X-Men: Days of Future Past, the famed mutant Scarlet Witch is hinted at through Quicksilver’s young sister and her pink dress – recalling her famed scarlet outfit. Despite this tease, subsequent movies set decades later failed to capitalize on her character. However, Scarlet Witch, portrayed by Elizabeth Olsen, has already appeared frequently throughout the Marvel Cinematic Universe, becoming a central figure in numerous narratives. Her journey in the MCU showcases her evolution as a character and the immense impact she has had on the broader Marvel universe, solidifying her place among its central figures.

9. Mister Sinister’s Essex Corp Was Established

Mister Sinister Could Be An Ideal MCU Villain

In the X-Men: Apocalypse post-credits scene, Mister Sinister’s introduction was teased specifically as genetic samples in the Weapon X facility were collected into a briefcase marked “Essex Corp.” This nod hinted at the potential introduction of the iconic X-Men villain. With his complex backstory and malevolent motivations, Mister Sinister could indeed become a compelling adversary within the MCU. Mister Sinister’s inclusion could add depth and intrigue to future storylines while exploiting his creepy visage to great effect. Moreover, with the animated series X-Men ’97 reviving the classic 1990s X-Men: The Animated Series, Mister Sinister’s appearance may be imminent.

8. Rogue Gaining Her Additional Powers Was Suggested

The MCU Can Feature A Fully-Powered Rogue

In X-Men: The Last Stand, Rogue’s storyline teased her potential evolution when she received the mutant cure, and it is shown later to be ineffective. This hinted at her eventual acquisition of superstrength and flight, a storyline from the comics where she absorbs the powers of Carol Danvers, aka Captain Marvel. The prospect of Rogue permanently absorbing Danvers’ abilities not only sets up an intriguing narrative but also presents an opportunity to seamlessly integrate her powers into the MCU. Rogue’s entrance into the MCU offers exciting possibilities for her character development, finally assuming her full range of abilities.

7. Jubilee Never Used Her Powers

The MCU Can Center On Jubilee

Jubilee, a beloved character from the comics and X-Men: The Animated Series, has been relegated to mere cameos in the X-Men movies, never truly using her powers or leading a storyline. This oversight undermines her significance in the comic books. However, the MCU presents an opportunity for redemption. By providing Jubilee with a narrative worthy of her comic book origins or reminiscent of her prominent role in X-Men: The Animated Series, the MCU could finally do justice to her character. Such a storyline would not only honor Jubilee’s importance but also enrich the MCU’s diverse pantheon of superheroes.

6. Proteus Was Established But Never Appeared

Proteus Would Make A Dynamic MCU Villain

In the X-Men movie universe, Proteus was confirmed to exist as Moira MacTaggert’s son in X-Men: Apocalypse, yet he never made an actual appearance. However, the MCU could now adapt his compelling comic book storyline. Proteus, possessing reality-warping abilities, offers a compelling narrative ripe for exploration in live-action. His complex relationship with his mother and his struggles with identity and power could be intriguingly portrayed on the big screen. By introducing Proteus into the MCU, Marvel Studios could delve into uncharted territory, offering fans a fresh take on this enigmatic character and further expanding the cinematic superhero landscape.

5. Marrow Featured Briefly In Deadpool

Marrow Is A Well-Known Anti-Hero

Despite being briefly glimpsed in Deadpool, Marrown’s potential as a live-action mutant was completely untapped. Marrow is spotted by Wade Wilson as he is wheeled through The Workshop, but the character is never seen again. Marrow’s mutant ability to manipulate and weaponize her bone structure presents a formidable threat. With proper development, her complex backstory and internal struggles could be explored, paving the way for a nuanced portrayal. As a villain in the MCU, Marrow could make a thrilling addition to the roster of adversaries, offering a captivating antagonist with layers of depth and motivation.

4. Karma Was Teased In X2

Karma Would Be An Ideal MCU X-Man

Several classic mutant characters were hinted at during X2: X-Men United, listed among William Stryker’s computer files examined by Mystique. A notable example from these is Karma, who never made an appearance in Fox’s X-Men movies. However, the Marvel Cinematic Universe presents an ideal platform to introduce her character properly. With her telepathic and possession abilities, Karma could be an invaluable asset to any X-Men team. Her inclusion could help diversify the team and bring a fresh dynamic to the MCU’s storytelling. As a highly consequential comic book character, Karma could proffer a fresh angle on the mutant telepaths depicted.

3. Captain Britain Was Listed In Stryker’s Files

Captain Britain Has Been Speculated For The MCU

Captain Britain was also hinted at Stryker’s files in X2: X-Men United, listed under his civilian name of James Braddock. However, Captain Britain has also not appeared in any live-action adaptation to date, despite fervent anticipation. Marvel fans have long awaited his debut in the Marvel Cinematic Universe, with much speculation swirling around Henry Cavill potentially portraying the iconic hero. Captain Britain typically leads a British mutant troupe known as Excalibur, based primarily on Muir Island. His long-awaited appearance would not only fulfill a decades-old tease but also expand the MCU’s global scope and superhero mythology.

2. Forge Was Also Listed In X2

Forge Could Be The MCU’s Next Iron Man

Forge was another famed X-Men character listed in Stryker’s computer files, who has been hotly anticipated in subsequent movies – with many expecting him to appear in X-Men: Days of Future Past. Forge has never been adapted to live-action, though it would be an ideal choice for the MCU. As a mutant with unparalleled technological prowess, Forge could seamlessly transition into the MCU as the new tech genius, potentially inheriting the mantle from Iron Man. His expertise could revolutionize the MCU’s technological landscape, while his mutant abilities could add a unique dimension to the superhero team dynamics.

1. Polaris Should Have Appeared

Polaris Was An Early X-Men Member

Polaris was also tantalizingly hinted at through Stryker’s files in X2: X-Men United and in Days of Future Past when Quicksilver’s mother references another sister. In the comics, Polaris is Magneto’s daughter and Quicksilver’s half-sister. However, she never materialized in Fox’s X-Men movies. Her significance in early X-Men comics and her enduring romance with Havok would have made her an ideal addition to the franchise – though the MCU can now redeem this. With her magnetic manipulation powers and complex character dynamics, Polaris’s rich backstory and relationships could offer compelling narrative opportunities, enhancing the interconnectedness of the MCU’s X-Men universe.