Continuity mistake: When Xavier is surrounded by a group of mutants in his subconscious, if you look at Quicksilver you can see that the colorist made his shirt flesh-colored. You can tell he is supposed to be wearing a shirt because the lightning bolt design is still going across his torso. (00:05:20)
Other mistake: When the Shadow King in his human form is passed out on the floor, his left hand appears to have at least six knuckles. (00:08:25)
Audio problem: Wolverine's mouth is closed when he says "Man, the weird dream I just had." (00:13:35)
Continuity mistake: When Xavier is explaining to Wolverine the importance of vigilance, Beast can be seen directly behind him. When the shot changes, Beast is no longer standing behind Xavier. (00:18:25)
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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