What if there are other universes, just like ours? With an infinite number of Earths? With uncountable versions of you? And what if we don’t have to look too far to find them? Maybe a mirror version ...

Believe it or not, Marvel's long-running What If? series turns 50 this year. That's a lot of alternate universe superhero stories. But there's still plenty more ground left to cover, as Marvel reveals ...