The Phoenix Saga (2): The Dark Shroud - S3-E4
Plot hole: After Professor X crashes his mini-jet onto the hospital roof and loses consciousness, he isn't discovered until Jean mentally locates him. An aircraft crashing on the roof would cause enough noise to immediately alert staff and anyone else in the hospital of his predicament. (00:09:15 - 00:15:45)
The Phoenix Saga (2): The Dark Shroud - S3-E4
Plot hole: Wolverine's enhanced sense of smell should have alerted him to Erik the Red's spy on the roof. Failing that, the video feed Erik the Red is receiving from the spy shows Wolverine, Beast and Professor X looking right in the spy's direction, so they would have seen him. (00:15:55)
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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