'Til Death Do Us Part: Part 1 - S2-E1
Deliberate mistake: When the Friends of Humanity are secretly filming their fight with Beast, Wolverine and Gambit, their cameraman is shown to be filming from the street behind a post box. However, the footage that they submitted to the news is merely the same camera angles shown from the viewer's perspective of the show. (00:11:45 - 00:13:20)
Deliberate mistake: When Gambit and Pierre are boating down the river, in the shot of Pierre saying "Yeah, we got word," the trees they pass on either side of the screen are just the same tree drawn repeatedly. (00:08:08)
Mojovision - S2-E11
Deliberate mistake: Some of the footage of the X-Men in action that Major Domo shows Mojo is clips from previous episodes, and even clips from the show's opening theme. (00:03:36 - 00:04:22)
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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