Marvel is making abig spectacle of announcing the full cast of the nextAvengers movie live on YouTube and social media. Most of the names arepredictable: Chris Hemsworth, Anthony Mackie, Florence Pugh, Paul Rudd, and variousstars of Marvels upcomingThe Fantastic Four: First Steps. But one name is definitely a surprise: Kelsey Grammer who has to be playing some version the X-Men character Beast.READ MORE: Is Marvel Hiding a Secret X-Men Movie?Grammer first played Beast in the Fox filmX-Men: The Last Stand way back in 2006. He then reprised the role (in CGI form, rather than the prosthetic makeup he wore inThe Last Stand) two years ago in a brief post-credits cameo inThe Marvels.It feels safe to assume this is the version of the character Grammer will play inAvengers: Doomsday.And if this Beastis in the film, it would be shocking if there werent at least a couple more X-Men characters joining him.Marvel acquired the rights to make X-Men movies when it purchased the 20th Century Fox film studio a few years ago. To date, they have made just one X-Men-centric film: Last summersDeadpool & Wolverine.They have also included a few other teases and hints about the X-Men in other films and shows, like Patrick StewartscameoinDoctor Strange in the Multiverse of Madness and an allusion to mutants inMs. Marvel.As to which other X-Men may join Grammer, that remains to be seen. So far the confirmedstars ofAvengers: Doomsdayinclude Chris Hemsworth as Thor, Vanessa Kirby as the new Invisible Woman from the upcomingThe Fantastic Four: First Steps, Anthony Mackie as Captain America, Sebastian Stan as Winter Soldier, Letitia Wright as theBlack Panther, Shuri, Paul Rudd as Ant-Man, Wyatt Russell as U.S. Agent, Tenoch Huerta Mejia as Namor, Ebon Moss-Bachrach as the Thing, Simu Liu as Shang-Chi, and Florence Pugh as Black Widow.Avengers: Doomsdayis scheduled to open in theaters on May 1, 2026. The film is now officially in production. You can follow along with the continuing cast announcements below.Get our free mobile appEvery Marvel Cinematic Universe Movie, Ranked From Worst to BestIt started with Iron Man and its continued and expanded ever since. Its the Marvel Cinematic Universe, with 35 movies and counting. But whats the best and the worst? We ranked them all.