[quote=@Nightrunner]
[@Gowi] What if he just assumed Xavier's identity after he fell in a coma? Or he just led the X-Men as J'ohnn J'onzz?

Either of those ideas work?
[/quote]

I mean, for what's it worth, I would rather have non-alien Xavier as my rival than the Martian Manhunter. Magneto's mutant nationalism needs a good foil to oppose it; otherwise, why would he be the rival to the X-Men? 

Edit: Had a brain fart whoops