The rules of time travel are murky at the best of times, regardless of what movie or TV show they apply to, and fans will always try to pick holes in the logic. That’s definitely been the case with Avengers: Endgame, which has invited all sorts of analysis and constructive criticism over the methods and machinations used by Earth’s Mightiest Heroes to both pull off the time heist in the first place, and then send Captain America back to return the Infinity Stones.
For the most part, it was left up to our imaginations as to what happened as Steve Rogers journeyed across time and space, even if it’s a tragedy that we never got to see the look on Red Skull’s face when his arch nemesis showed up on Vormir, handed the Soul Stone right back to him and then f*cked off without any explanation.
However, a new theory has pointed out that one branched timeline was never fixed, and it’s all Hawkeye’s fault. When trying to figure out time travel in the first place, following a couple of mishaps involving Scott Lang, Clint Barton suits up and visits his farmhouse five years previously, taking a baseball glove to prove that his jump back had worked.
It never gets mentioned again for the remainder of Endgame, but the fact Clint had removed something from a past timeline and brought it to a present one would surely cause some kind of butterfly effect that would reverberate through the multiverse. As it stands, though, the test run is swiftly forgotten about as the Avengers deal with the much bigger fish they’re preparing to fry, namely a daring heist to gather all of the Infinity Stones at once and reverse the damage done by Thanos’ snap.