Other mistake: When the Lady Gardener touches the flower on her table, it instantly dies, which elicits a shocked reaction from her. This show establishes that mutant powers begin to manifest during puberty, and this character is middle-aged. A character that has been living with their powers for that long shouldn't be shocked at what her powers do. (00:03:56)
Other mistake: When the tank falls through the hole in the bridge, the tank's occupants are impossibly shown to be clinging to the edge of the hole at the same time the tank is going over the edge, as if the tank and the occupants were occupying the same space. (00:09:40)
Other mistake: After Gambit explodes the statue that was about to fall on Wolverine, there is no debris shown to be flying around them even though the statue was collapsing towards them. (00:16:30)
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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