The Marvel Cinematic Universe is set to introduce one of its most formidable and enigmatic characters as the main villain in the upcoming Fantastic Four reboot: Galactus, the Devourer of Worlds. This cosmic entity, whose hunger for entire planets has shaped countless storylines in Marvel Comics, is finally making his way to the big screen. But who is Galactus, and what makes him such a compelling antagonist for the Fantastic Four?