Continuity mistake: During the last great battle with Apocalypse, Beast hurls an entire automobile at Storm, and she recoils in fright. Before the car crushes Storm, Psylocke slices the automobile in half, with the two halves separating by several feet (at least 10 feet) before the shot changes. But in the next shot, the two halves of the car crash down on either side of Storm, separated by only a couple of feet.
Continuity mistake: The length of Eric's beard changes when he gets his new powers from Apocalypse.
Continuity mistake: While Eric is talking with Xavier beside Apocalypse and the others he takes a few steps but suddenly he is 60 feet away.
Continuity mistake: After Apocalypse pins Quicksilver to the ground, while he is holding Raven the space between them changes between shots.
Answer: Psylocke is purposefully shown literally just walking away after the dust has settled. She could very well show up in another film somewhere along the line but nothing has been confirmed as of yet.
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