MCU Phase 4: 10 Mind-Blowing Secrets & Theories You Need To Know
3. Multiverses
Multiverses really are less of a theory for Phase 4 and more a known fact. With Doctor Strange 2 set to be called Doctor Strange In The Multiverse Of Madness, we're getting multiverses. It's a done deal. The theory goes though that it will extend beyond that single film and will become a defining part of the MCU moving forward.
The Infinity Saga is pretty much all we've known in the MCU to date, and that involved half the cast being killed off. Yes, they all came back, but at the cost of Iron Man, Black Widow, Vision and (kind of) Captain America and Gamora. At the very least, the version of Gamora we knew.
Moving forward then, they'll need to raise the stakes even higher. This could mean bringing multiverses into the fray, with the heroes fighting wars on different fronts. It also offers a bit of an out for the Fantastic Four and the X-Men to be introduced with relative simplicity.
That, of course, could be a bit of a cop out, but then a lot of the MCU plot points have survived on the strength of the writing and characterisation around them.