Factual error: When a parachuting Xavier is about to land, you can see his legs are bent at the knee to brace for landing. Since Xavier is a paraplegic, he shouldn't be able to do this. (00:19:14)
Factual error: When Senator Kelly is giving his campaign speech, the U.S. flag behind him is missing one stripe and has at least two too many stars. (00:19:30)
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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