Credit: 20th Century StudiosMarvel Studios is getting closer to the release of Avengers: Doomsday (2026), and with every passing month, new details continue to emerge about what could become one of the biggest crossover events in MCU history.
That isn’t particularly surprising. Marvel has spent years building anticipation around the film, especially after confirming that Robert Downey Jr. will return to the franchise as Doctor Doom. But as excitement grows, so do the leaks, promotional reveals, merchandise teases, and behind-the-scenes details.
The latest reveal centers on the X-Men.
While fans already knew Marvel was bringing several Fox-era mutants into the MCU, newly surfaced promotional material appears to offer a much clearer look at how at least one iconic character will be reimagined for the film. In the process, Marvel may have quietly confirmed a significant visual retcon for one of the franchise’s most recognizable heroes.
The Fox X-Men Are Officially Joining the MCU
One of the biggest selling points of Avengers: Doomsday is its enormous cast.
Marvel has already confirmed that several beloved characters from the Fox X-Men universe will return alongside Earth’s Mightiest Heroes and the Fantastic Four. The film effectively brings together multiple generations of Marvel storytelling for the first time on such a massive scale.
Among the returning mutants are James Marsden as Cyclops, Patrick Stewart as Professor X, Ian McKellen as Magneto, Channing Tatum as Gambit, Kelsey Grammer as Beast, Alan Cumming as Nightcrawler, and Rebecca Romijn as Mystique.
For longtime Marvel fans, that lineup is remarkable on its own. Many of these actors helped define Marvel movies before the MCU even existed. Now they will reportedly stand alongside MCU heroes as Doctor Doom’s threat grows across the Multiverse.
Beast Gets Another New Look
Among the returning X-Men, Beast appears to be receiving another redesign.
Hank McCoy has undergone several visual changes throughout Fox’s X-Men films, first through Kelsey Grammer and later through Nicholas Hoult’s younger version of the character. After Grammer returned in the post-credits scene of The Marvels (2023), fans assumed that look would carry into Avengers: Doomsday.
However, newly surfaced promotional artwork suggests Marvel has other plans. The image features several confirmed characters and offers a new glimpse at Beast’s appearance ahead of the film’s release.
A Different Direction for Beast
The biggest change is Beast’s costume—or lack of one.
For the first time in live-action, Beast appears shirtless, showing off his blue fur-covered torso and arms. Previous versions of the character always wore some form of upper-body clothing, whether it was a uniform, jacket, or lab coat.
The artwork suggests Marvel may be emphasizing Beast’s physical side more than his scientist persona. Other merchandise tied to the film appears to support that idea.
Recently revealed Marvel Legends figures show Beast without a shirt while still wearing the glasses first seen in The Marvels. The figure also includes an X-Men belt, matching details found in the promotional artwork.
Marvel has not officially confirmed that this exact design will appear on screen. However, the consistency across multiple pieces of merchandise has convinced many fans that this may be Beast’s new look for Avengers: Doomsday.
The X-Men May Arrive Through a Multiversal Collision
The redesign isn’t the only major talking point surrounding the X-Men.
Footage shown privately during CinemaCon reportedly provided new clues about how the Fox mutants enter the story.
According to attendee descriptions, Professor Xavier is shown looking out a window at the X-Mansion as an intense flash of light approaches. The moment appears to signal a multiversal incursion, potentially pulling the X-Men directly into the growing conflict surrounding Doctor Doom.
If those reports are accurate, Marvel is setting up a collision between multiple realities.
Rather than immediately joining forces, the Avengers and X-Men may initially find themselves on opposing sides. Early footage reportedly hinted at tension between the groups before they eventually unite against Doom.
A Crossover Like Never Before
CinemaCon attendees reportedly witnessed several memorable moments involving the X-Men and MCU heroes.
One sequence featured Channing Tatum’s Gambit facing off against Shang-Chi, played by Simu Liu. Another showcased Mystique battling Yelena Belova before using her shape-shifting abilities to create a chaotic fight involving multiple versions of the assassin.
Those moments generated some of the strongest reactions from the crowd and offered a glimpse of the scale Marvel appears to be targeting.
By the time Avengers: Doomsday arrives, the Avengers, Fantastic Four, and X-Men could all be fighting for survival as their universes collide.
Marvel’s Mutant Future Is Taking Shape
Marvel has spent years laying the groundwork for the X-Men’s arrival in the MCU, and Avengers: Doomsday appears ready to accelerate that process in a major way. Between the return of iconic Fox-era characters, growing evidence of Beast’s redesigned appearance, and reports of a multiversal showdown involving multiple superhero teams, the film is shaping up to be far more than a traditional Avengers adventure.
With Doctor Doom at the center of the chaos and several realities seemingly headed for a collision course, Marvel’s biggest crossover yet may finally be taking shape. And if these latest reveals are any indication, fans should expect even more surprises before December 18 arrives.
