
Marvel Studios has reportedly chosen three intriguing villains to go up against the X-Men in the upcoming reboot movie. A fresh new take on the X-Men under the MCU banner is still in development, with Thunderbolts* director Jake Schreier rumored to have been tapped to helm the reboot. While the movie is now unlikely to be released in 2027 following Avengers: Doomsday's delay from May 2026 to December 2026, the anticipation surrounding the MCU's take on the X-Men is still high.
One of the big question marks in the upcoming reboot is the identity of the X-Men's new antagonist. With an extensive rogue's gallery, names like Mojo, Nimrod, Apocalypse, and Onslaught are being thrown in the ring by fans, but a new report from Alex Perez of The Cosmic Circus has revealed which villains Marvel Studios are eyeing for the MCU's first-ever X-Men movie.
The 3 Marvel Villains Rumored for the MCU's X-Men Reboot
Nathaniel Essex/Mr. Sinister

Given that Mr. Sinister (aka Dr. Nathaniel Essex) has been rumored to be the main villain in one of the drafts of Marvel Studios' X-Men reboot in Phase 7, his inclusion in the new report isn't surprising.
In Marvel Comics, Dr. Essex's fascination with mutation and human evolution ultimately leads to his downfall, leading to his transformation into Mr. Sinister after encountering another X-Men villain: Apocalypse. As Mr. Sinister, he serves as a formidable foe against the mutants due to his vast array of abilities, which include immortality, telepathy, superhuman strength, shapeshifting, and telekinesis.
X-Men '97 proved how Mr. Sinister can be a problem for the mutants due to his continued torment of the team, and the same relentless pursuit could happen in the upcoming live-action X-Men reboot.
It's possible that Mr. Sinister's fascination would lead him to pursue experiments against the X-Men, and he could potentially team up with the government to achieve his goal.
Senator Robert Kelly

In the stories of the X-Men, the mutants not only had to deal with the powerful villains, but they also had to fight against top decision makers in the government who questioned their existence. One of them is Senator Robert Kelly.
Senator Kelly has been a harsh critic of the mutants, believing they are a threat to national security. In Marvel Comics, he was instrumental in promoting the mutant registration act, ultimately leading to his death caused by the assassination by the Brotherhood of Mutants. His demise essentially kicked off the events that led to the Days of Future Past timeline, where the Sentinels hunted down the mutants and conquered the planet.
Senator Kelly's inclusion in the upcoming reboot could hint that the MCU will deal with the ramifications of the mutants' existence right off the bat, similar to how Captain America: Civil War pushed the Sokovia Accords to the forefront.
His presence could also tease the eventual passing of the mutant registration act, meaning that an adaptation of Days of Future Past set in the MCU could happen sometime in Phase 7.
Bolivar Trask

As a renowned weapons builder, Bolivar Trask is responsible for creating the Sentinel Program (aka the killing machines that targeted and eventually eradicated the mutants in a dystopian future).
Trask's hatred toward the mutants has been his driving force in creating the Sentinels, and the same motivation could be showcased in Marvel Studios' reboot.
Moreover, Trask's addition to the X-Men reboot suggests a grim future in which the Sentinels will be brought into action and cause a massive conflict against Charles Xavier and his team at some point in Phase 7. Trask could also be the main puppet being controlled by Mr. Sinister in the shadows to ensure that he will make the Sentinels as dangerous as possible.