'Til Death Do Us Part: Part 2 - S2-E2
Other mistake: The show establishes that Jubilee is Chinese-American, but after she accidentally blasts Wolverine, the way she pronounces "Sorry" is the way the word is typically pronounced by Canadians (most of the show's voice cast, including the actress who voiced Jubilee, are Canadian). (00:11:00)
'Til Death Do Us Part: Part 2 - S2-E2
Other mistake: When Mr. Sinister and the Nasty Boys are fleeing from the X-Men, their plane takes off a split-second after they have all disappeared into the treeline. (00:19:10)
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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