Continuity mistake: The picture of Jean and Cyclops Wolverine has framed shows them against a yellow-orange background, and Cyclops' sunglasses are red. When the picture is shown again at the end of the episode, the background is now white and Cyclops' sunglasses are gray. (00:08:14 - 00:20:44)
Continuity mistake: When Wolverine finds the unconscious Cyclops, Cyclops' sleeve is rolled all the way down. A couple of shots later, the sleeve is now rolled halfway up. (00:16:42)
Continuity mistake: When Leech telekinetically splits up the mob, on his left are a man with a light blue shirt, followed by a man with an orange shirt, and man with a light blue shirt behind him. On his right are a man with a green jacket and yellow shirt, a man with an orange jacket and pink shirt behind him, and lastly, a man with a blue jacket and yellow shirt. When the shot changes, the men have not only swapped sides, but now it is two men in light blue shirts in front of the man in the orange shirt, and the man with the orange jacket and pink shirt is now just wearing an orange shirt, and he is standing in front of the man with the green jacket and yellow shirt, and the man with the blue jacket and yellow shirt is in front of him. (00:06:05)
Continuity mistake: After Jean and Cyclops first kiss after she tells him to relax a little, his left arm is around her shoulder and it suddenly jump cuts to his side with his hand in his pocket. (00:05:37)
Continuity mistake: When Wolverine punches his lefthand claws into the wall, it is at bottom of a slab of concrete, and to the left of where four slabs intersect. When the shot changes, the puncture is now closer to the middle-right area of a slab. (00:13:16)
Continuity mistake: When Jean is saying "Where am I? What's happening?", she has a lock of hair draped over her left shoulder that suddenly turns a darker shade of red. (00:13:26)
Continuity mistake: When Wolverine is saying "Cyke has his problems, but he don't smell like a Morlock," Gambit's bare neck is visible, when it should be colored black because of his headgear. (00:14:11)
Continuity mistake: When Tar Baby traps the mob inside the subway platform, he seals off the stairs with a wall of tar. When Cyclops and Jean have arrived to intervene, the wall of tar is now in front of the turnstiles. (00:06:24)
Continuity mistake: When Storm is having a flashback to her childhood in a fit of claustrophobia, she is depicted as a Caucasian girl with red hair. (00:03:35)
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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