How Avengers: Endgame Could Secretly Set Up The MCU X-Men
1. The Cost Of Removing The Stones Theory
Despite the fact that Endgame's internal logic spends a long time establishing that the various branches of alternate realities created by the Avengers meddling in the past have to be cut off for the good of the timeline, some changes are unavoidable. Also, the creation of some of those alternate timelines is very deliberate, as with Captain America splintering time to create his own happy ending.
There's also something else the Ancient One says that could be crucial. She tells Banner that removing the Stones from her timeline would be disastrous for her future, because of what they're protecting the universe from.
Here's what she says:
"The Infinity Stones create what you experience as the flow of time. Remove one stone and that flow splits. Now, this may benefit your reality, but my new one, not so much. In this new branch reality, without our chief weapon against the forces of darkness, our world would be over-run and millions would suffer. Tell me, Doctor, can your science prevent all that?"
It's interesting, then, that at the end of the movie, the Stones have been taken out of the timeline and trapped in an infinite loop. They no longer exist to protect the realities created from the point of Cap taking them back in time to protect from the "forces of darkness" that would "over-run" the world.
The most important part of that quote is the start: ignoring the branches, The Ancient One says the Stones create the flow of time. In essence, it could be possible that their removal from the timeline causes issues with the way time flows and the way alternate realities co-exist. What if one of those alternate realities - where mutants already exist - collapses and merges with the mainline or is threatened so much that the X-Men open up the multiverse to save their own universe and welcome in mutants?
What do you think, could either of these theories be real? Share your reactions below in the comments thread.