The Juggernaut Returns - S3-E17
Other mistake: During the "Previously on X-Men..." segment before the show's intro, it shows the Juggernaut landing in the ocean and walking across the ocean floor after Gladiator had hurled him away. However, Juggernaut's fate was never actually shown after Gladiator threw him. He was only seen fading off into the distance. (00:00:50)
The Juggernaut Returns - S3-E17
Continuity mistake: When Gambit is repairing the school bus, his sleeves are pink with blue patches when they are normally black with pink patches. (00:06:10)
The Juggernaut Returns - S3-E17
Continuity mistake: When the new Juggernaut is falling towards the film studio, he is shown to be falling at a diagonal angle. When he crashes through the ceiling, he is falling straight down. (00:16:10)
The Juggernaut Returns - S3-E17
Continuity mistake: When Wolverine is saying "Make your move tough guy," to Juggernaut, Cyclops' gloves are the same color as the ground and his normally yellow belt is red. (00:20:25)
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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