Revealing mistake: When Gambit bumps the toggle switch that increases the Danger Room difficulty, you can see it actually moves itself before his elbow touches it. (00:02:55)
Revealing mistake: When the assassin is handing Bobby the tithe box, the assassin's left hand passes through the chair Bobby was sitting in. (00:11:15)
Revealing mistake: When Bella Donna is preparing to shoot a blast of energy at Rogue, her body passes through the left hand of the man on her left that was holding her back. Half of her cloak then disappears as she strides forward. (00:14:42)
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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