Days of Future Past: Part 1 - S1-E11
Trivia: After Bishop travels into the past, he hears one kid telling another that they will be playing the new Punisher game "Assassin." When the Punisher was first being developed, he was originally going to be called The Assassin.

Trivia: One of the images in Gambit's mind-scan is of fellow Marvel Comics superhero Ghost Rider. (00:07:45)
Night of the Sentinels: Part 1 - S1-E1
Trivia: The beginning of this series sees a young mutant serving as a proxy for the audience, where they discover their mutant powers, try to elude sinister forces that are after them, and meet and later join the X-Men along the way. Showrunner Larry Houston claims director Bryan Singer borrowed this idea for the first X-Men film, substituting Rogue for Jubilee.
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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