
The Phoenix Saga (1): Sacrifice - S3-E3
Revealing mistake: During the opening battle in outer space, when the green ship uses its tail to tear a hole into the larger ship, you can see the tear slightly shift downward. (00:01:47)

The Phoenix Saga (1): Sacrifice - S3-E3
Revealing mistake: After the X-Men rescue Dr. Corbeau and retreat back to the shuttle, they come upon a room with crew members passed out on the floor. Keep an eye on Wolverine in the background on the right side of the screen and you will see him literally walk through a door panel. (00:17:28)

The Phoenix Saga (1): Sacrifice - S3-E3
Revealing mistake: When Cyclops is saying "Can this thing still fly," the purple coloring of the buttons behind him on the left shift up, while their black outline remains in place. (00:17:59)
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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