Other mistake: After Magneto says "Trust me, you'd rather not know," a hole appears in his pants around his right hamstring and then quickly disappears. (00:02:50)
Other mistake: When Xavier asks Magneto how much further they have to reach the top of the cliff, Magneto tells him he would rather not know, suggesting they still have a long way to go. However, in the wideshot of the sky-riders flying in to attack the two, you can see Magneto is about three times the length of his own body from the top, and according to the book "X-Men: The Art and Making of the Animated Series," Magneto is 6 feet tall. This means he is only about 20 feet, give or take, from the top, which isn't all that far in terms of climbing a cliff. (00:02:44)
Mojovision - S2-E11
Other mistake: When Jean is trying to dodge Spiral's teleporting blast, she ends up tripping on a power cord running across the floor. An electronics store wouldn't have a power cord running across its floor for this very reason. They would be begging for a lawsuit if they did. Her foot is also closer to the wall in the first shot than in the second shot. (00:07:30)
Other mistake: When Jean is bringing a tray of food to Beast, the liquid in the glass is not oscillating. (00:09:38)
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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