Other mistake: When Bella Donna is saying that Gambit was wise to leave the Thieves Guild, there is a black horizontal line on Gambit's right cheek that disappears and reappears in sync with his blinking.
Continuity mistake: The glove on Magneto's right hand disappears after Mr. Sinister blasts him in the back. (00:17:20)
Mojovision - S2-E11
Continuity mistake: When Wolverine and Jean Grey are being shuffled in to their television program, Wolverine's face is yellow. (00:15:35)
Mojovision - S2-E11
Continuity mistake: When Cyclops and Storm are about to be shuffled in to their television program, Jubilee can be seen standing between Wolverine and Storm, despite the fact that she was not among the X-Men that were abducted by Spiral, nor is she seen again for the rest of the episode. (00:10:05)
Continuity mistake: When Rogue is crashing through several levels of the mansion, the last one she crashes through is Storm's greenhouse and you can see through the windows that it is light outside. When she crashes through the ceiling of the mansion a split second later, it is suddenly dark outside. (00:08:15)
Other mistake: After Rogue knocks Gambit over, Gambit is in the foreground and Rogue is in the background. Despite this, the heel of Rogue's right boot appears in front of Gambit's left foot. (00:06:32)
Other mistake: When the Blob picks up the bucket of ice cream, he says "Oh boy, tutti frutti!", but the label on the bucket says "Vanilla." (00:03:50)
Time Fugitives: Part 2 - S2-E8
Continuity mistake: Bishop is shown trying to disperse the crowd at the quarantine site. When Cable appears on the rooftop ready to snipe him, Bishop is shown walking among the crowd. When Cable relents, Bishop is back trying to disperse the crowd. (00:06:15)
Time Fugitives: Part 1 - S2-E7
Continuity mistake: When Wolverine slashes through the fence, Gambit and Bishop can be seen already running towards the fence while Cyclops, Jean Grey and Beast stand behind. When the shot changes, Gambit is the last person to run through the hole in the fence with Cyclops, Jean Grey and Beast ahead of him. (00:17:40)
Time Fugitives: Part 1 - S2-E7
Revealing mistake: When Wolverine is free falling from the Blackbird, his left leg passes through Cyclops' right arm. (00:11:40)
Time Fugitives: Part 1 - S2-E7
Continuity mistake: After Storm informs Cyclops that a mob is attacking Bishop, a shot of the rest of the team in the Blackbird shows that Gambit's neck is flesh colored when it is supposed to be black from wearing his headgear (this is corrected when the scene is reprised in the next episode). (00:11:25)
Other mistake: When Rogue drops the mug of coffee onto the floor, you can see that the coffee touches her boot, yet her boot does not get any stains on it. (00:04:05)
Continuity mistake: Gambit's sleeves turn from black to pink when Bella Donna reveals to him that she double crossed the Thieves Guild. (00:13:25)
'Til Death Do Us Part: Part 1 - S2-E1
Continuity mistake: The blast damage Jubilee causes to the door of the War Room suddenly disappears after Morph (in the guise of Rogue) exits. (00:15:00)
'Til Death Do Us Part: Part 1 - S2-E1
Deliberate mistake: When the Friends of Humanity are secretly filming their fight with Beast, Wolverine and Gambit, their cameraman is shown to be filming from the street behind a post box. However, the footage that they submitted to the news is merely the same camera angles shown from the viewer's perspective of the show. (00:11:45 - 00:13:20)
'Til Death Do Us Part: Part 2 - S2-E2
Continuity mistake: When Morph parks the police car outside the gates of the X-Mansion, the front half of the car is in the immediate pathway of the gate. A couple of shots later, the entire car is parked along the curb. (00:02:50)
'Til Death Do Us Part: Part 1 - S2-E1
Continuity mistake: In the first shot of Rogue, Storm, Wolverine and Gambit watching Professor X's holographic message, Gambit's trenchcoat is colored yellow and his hair is colored black. The animators must have confused him for Jubilee at first, because those are the colors of her jacket and hair. (00:12:50)
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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