X-Men Confirmed to Return in Marvel’s Avengers: Doomsday

Key Points

• Marvel’s latest teaser confirms the X-Men will appear in Avengers: Doomsday.
• The clip features Ian McKellen’s Magneto, Patrick Stewart’s Charles Xavier, and James Marsden’s Cyclops.
• The teaser debuted ahead of Disney’s blockbuster Avatar: Fire and Ash.
• Doomsday marks the MCU debut of McKellen and Marsden, while Stewart reprises Xavier in a new timeline.
• Directed by Anthony and Joe Russo, the film releases December 18, 2026.

The Teaser Reveal

Marvel Studios has officially confirmed the return of the X-Men in Avengers: Doomsday. The third teaser for the highly anticipated crossover dropped Tuesday, spotlighting Magneto, Xavier, and Cyclops in a somber montage.

The footage opens inside the ruins of Xavier’s School for Gifted Youngsters, before cutting to an emotional exchange between Xavier and Magneto. Cyclops is then shown unleashing a massive optic blast as towering figures—likely Sentinels—loom in the background.

Magneto’s Voiceover

The teaser is underscored by Magneto’s haunting narration: “Death comes for us all. It’s all I know for sure. The question isn’t ‘are you prepared to die?’ The question is ‘who would you be when you close your eyes?’”

The clip ends with text promising the X-Men’s return in Avengers: Doomsday, followed by a countdown to the film’s release.

X-Men in the MCU

This marks the MCU debut of Ian McKellen and James Marsden, who previously starred in Fox’s X-Men franchise beginning in 2000. Patrick Stewart, meanwhile, reprises Xavier after appearing in Doctor Strange in the Multiverse of Madness (2022).

Other mutants already introduced into the MCU include Hugh Jackman’s Wolverine in Deadpool & Wolverine and Kelsey Grammer’s Beast, who appeared in a post-credits scene for The Marvels. Additional X-Men expected in Doomsday include Beast, Nightcrawler (Alan Cumming), and Mystique (Rebecca Romijn).

The Ensemble Cast

Directed by Anthony and Joe Russo, Avengers: Doomsday will feature an expansive roster:

• Robert Downey Jr. returns as the villain Doctor Doom.
• Avengers alums Anthony Mackie, Sebastian Stan, Paul Rudd, and Tom Hiddleston reprise their roles.
• The Thunderbolts team, led by Florence Pugh, David Harbour, Lewis Pullman, Wyatt Russell, and Hannah John-Kamen, joins the fight.
• The Fantastic Four, played by Pedro Pascal, Vanessa Kirby, Joseph Quinn, and Ebon Moss-Bachrach, also appear.

Context: Why It Matters

The inclusion of the X-Men marks a pivotal moment for the MCU, uniting Marvel’s most iconic superhero teams under one storyline. Since Disney’s acquisition of Fox in 2019, fans have speculated about when mutants would officially join the MCU. Doomsday delivers that long-awaited crossover.

What Happens Next?

With teasers spotlighting Steve Rogers, Thor, and now the X-Men, Marvel is building anticipation for what promises to be one of its most ambitious films yet. Avengers: Doomsday arrives in theaters December 18, 2026, setting the stage for the MCU’s next era.