The Dark Phoenix (4): The Fate of the Phoenix - S3-E14
Continuity mistake: When Earthquake knocks out Gambit and Storm, he and Hussar are offscreen to the viewer's left. When the shot changes, Hussar is standing directly behind where Gambit and Storm's heads are pointing. (00:10:54)
The Dark Phoenix (4): The Fate of the Phoenix - S3-E14
Continuity mistake: When Cyclops and Jean are hiding in the shallow alcove, as he is saying there's so much he wants to say to her, his teeth alternate between being white and flesh-colored. (00:13:56)
The Dark Phoenix (4): The Fate of the Phoenix - S3-E14
Revealing mistake: In what appears to be an animation error, when Cyclops shoots his optic beam after he and Jean emerge from hiding, his bandolier is absorbed into his uniform. (00:14:25)
The Dark Phoenix (4): The Fate of the Phoenix - S3-E14
Continuity mistake: When Lilandra slams her first down onto the control panel, the appearance of the control panel changes between shots. (00:17:14)
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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