The Dark Phoenix (3): The Dark Phoenix - S3-E13
Plot hole: When the X-Men are on the roof of the Hellfire Club confronting the Dark Phoenix, Beast suddenly has some kind of hi-tech backpack-like device, despite being held captive without it in the previous episode, and never shown having one when he entered the club in the episode that preceded that one. (00:03:00)
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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