The Phoenix Saga (2): The Dark Shroud - S3-E4
Revealing mistake: When Lilandra is saying to Xavier "I have seen your face a thousand times in my mind," the edge of an animation cel is visible around the parietal area of Xavier's head. (00:20:24)
The Phoenix Saga (2): The Dark Shroud - S3-E4
Revealing mistake: When Jean is saying that she feels strange, the edge of an animation cel is visible moving left and right under her pillow. (00:05:27)
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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