Continuity mistake: When Magneto is saying "Mutants will come to me by the thousands," he raises his right fist up near his face. He then begins lowering his hand, and when the shot changes, it is instantly down at his side. (00:20:29)
Continuity mistake: When Jubilee blasts Sabretooth through walls of the War Room and outside, it is shown to be on the mansion's ground level. Many other episodes however depict the War Room to be in the underground levels of the mansion, specifically in the episode "The Unstoppable Juggernaut" where the War Room is still intact after the mansion is destroyed from the ground up.
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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