Credit: Inside the MagicThe Marvel Cinematic Universe (MCU) may have just dropped a massive hint at its upcoming crossover event. A newly leaked Reddit video shared by user @booletproof_dummy appears to show parts of a Sentinel — the towering, mutant-hunting machines synonymous with X-Men lore — on the set of Avengers: Doomsday. The footage, filmed clandestinely, seems to depict Xavier’s Institute, the iconic home of the X-Men, in ruins. This leak could confirm months of speculation about the X-Men’s involvement in the MCU’s most ambitious project to date.
The Sentinels: A Marvel Legacy
The Sentinels are no mere Easter egg. First introduced in X-Men #14 (1965), these formidable robots were created to detect and destroy mutants, symbolizing humanity’s fear of the unknown. Their role in the comics has always been pivotal, from storylines like Days of Future Past to House of X. Fans have already seen an iteration of the Sentinels in the 2014 film X-Men: Days of Future Past, where they posed a dystopian threat that pushed mutants and humans alike to the brink of extinction. Their potential presence in Avengers: Doomsday signals not only a continuation of their storied history but also a dramatic escalation in the MCU’s stakes.
Inside view of the set of Avengers Doomsday
byu/booletproof_dummy inAvengers
X-Men and the MCU: A Growing Connection
So far, details about the X-Men’s role in Avengers: Doomsday have been kept tightly under wraps, but the groundwork for their inclusion has been laid over the past several MCU installments. The first major hint came in Doctor Strange in the Multiverse of Madness (2022), which featured Sir Patrick Stewart reprising his role as Charles Xavier, albeit in an alternate universe. This was followed by Ms. Marvel (2022), where Kamala Khan was revealed to be a mutant, a subtle yet groundbreaking nod to the X-Men’s eventual arrival.
Familiar Faces, New Alliances
Marvel Studios confirmed during a live stream event that multiple stars from the Fox X-Men universe will be returning for Avengers: Doomsday. Fans were thrilled as the names of X-Men alumni lit up the screen, including Patrick Stewart (Professor X), Ian McKellen (Magneto), James Marsden (Cyclops), Alan Cumming (Nightcrawler), Rebecca Romijn (Mystique), Kelsey Grammer (Beast), and even Channing Tatum, who made his long-awaited debut as Gambit in Deadpool and Wolverine (2024) after years of speculation. This announcement has only fueled excitement about how these iconic characters will fit into the MCU’s multiverse saga.
Avengers vs. X-Men? Or Something Bigger?
Perhaps the most tantalizing rumor is that Avengers: Doomsday will feature a dramatic confrontation between the Avengers, the Fantastic Four, and the X-Men. Early leaks have suggested that the film’s plot will explore ideological clashes between the teams before uniting them against a common enemy: Doctor Doom. The presence of Sentinels in the leaked footage suggests that mutant persecution might only be one of the plot points, with the main narrative focusing on incursions and colliding universes, as previously mentioned in Doctor Strange in the Multiverse of Madness. Doom’s involvement hints at a larger scheme tied to multiversal chaos and domination, raising the stakes to unprecedented levels.
The Road to Doomsday
Set to release on May 2, 2026, Avengers: Doomsday will serve as the culmination of the MCU’s Multiverse Saga, bringing together heroes from across its sprawling cinematic universe. From Wanda Maximoff’s reality-warping exploits in WandaVision (2021) to the time-bending chaos of Loki (2021–present), Marvel Studios has been steadily building toward this moment. With the X-Men now seemingly in the mix, the possibilities are endless.
Fan Reactions and Speculation
As expected, the leaked footage has sent fans into a frenzy. Reddit threads are buzzing with theories about how the Sentinels and Xavier’s Institute fit into the film’s narrative. Is this a flashback, an alternate timeline, or the MCU’s primary reality? Could the Sentinels’ inclusion set the stage for an adaptation of the House of M storyline or even a full-fledged Avengers vs. X-Men event?
Whatever the case, the MCU’s future looks brighter (and more complex) than ever. One thing is certain: the clash of worlds in Avengers: Doomsday is shaping up to be a cinematic event of unprecedented proportions. Keep an eye on Reddit and other forums for more leaks and theories as we inch closer to Marvel’s most ambitious crossover yet.
Are you excited to see these heroes face off against Doom? Let us know in the comments.