How Magneto Fits Into X-Men: Dark Phoenix; Genosha Confirmed In X-Men: Dark Phoenix, Magneto will be ruler of the island nation of Genosha and will run into Jean Grey. It’s gradually becoming clear that next year’s X-Men: Dark Phoenix will be very different to the comic book story. One of the major differences is clearly the fact that Michael Fassbender is reprising the role of Magneto in the film. The character wasn’t part of the original comic book storyline, and fans have been excitedly speculating as to just what role the Master of Magnetism will play.