Marvel Comics once decided to give one of its most powerful villains, the Beyonder, a shocking new origin, connecting him to mutants and the Inhumans. However, over time, the retconned history of the reality-manipulating villain has been forgotten — as it was later revealed the Beyonder was just one of many Beyonders, an alien race who are responsible for the different Secret Wars that have pitted different realities against one another.
The Beyonder made his first appearance in Marvel Super Heroes Secret Wars #1 by Jim Shooter and Mike Zeck, as he assembled the greatest heroes and villains from across the cosmos to fight on Battleworld. Described as the most powerful being in the Multiverse, Beyonder used his immeasurable reality-warping powers to create future Secret Wars and make Marvel's most powerful entities look weak in comparison. However, Marvel Comics retconned the original Secret Wars in New Avengers: Illuminati, where it was revealed Xavier found out the true Inhuman history behind the Beyonder, which also tied the villain to mutants.
Related: Even Moon Knight Admits He Isn't Actually a Marvel Hero
In New Avengers: Illuminati #3 by Brian Michael Bendis, Jimmy Cheung, and Mark Morales, Professor X revealed the true nature of the Beyonder. In the issue, Xavier reveals during the original Secret Wars, he used his powers to look inside Beyonders mind, which showed him the Beyonder was actually an Inhuman — and not only that, but he was also part mutant. According to Charles Xavier, he had mutant genes before the Terrigen Mist unlocked his full Inhuman nature.
Later, the Illuminati met with the Beyonder, where the all-powerful being bowed down to Black Bolt, revealing his allegiance to the Inhuman Royal Family.
Read more on screenrant.com