'Til Death Do Us Part: Part 1 - S2-E1
Continuity mistake: When the bartender is asking Beast if he knows the President, there is a single red striped 11 ball on the pool table in the background. When the shot changes, there are now what appears to be the solid green 6 ball, and the purple striped 12 ball. (00:11:04)
Continuity mistake: When Rogue is calling out to Gambit just before Jean and Senator Kelly exit the mine shaft, the X logo on her chest is a yellow X on a red background, when it should be a black X on a red background. (00:17:57)
Continuity mistake: When Gambit is saying "You got me in the guild, Bobby," you can see on the wall across the hall that there is a switch that is the same red color as the wall. A few shots later, the switch is now gray. (00:10:18)
Continuity mistake: When the External selects Bobby to be the chosen one for the Guild of Thieves, she turns his jacket red and his gloves gray and fingerless. When he is shown again a few shots later, his jacket is now green, and his gloves are brown, with only the thumbs being fingerless. (00:06:53)
Continuity mistake: When the Danger Room doppelganger of Omega Red confronts Cyclops, its left arm is pointed down. When the shot changes, its left hand is raised at almost shoulder level. (00:03:01)
Continuity mistake: When Jubilee is heading to the store, the driveway of the mansion is shown to have a roundabout by the front door, and a small path leading to the front gate. However, the previous episode 'Til Death Do Us Part: Part 1 showed the driveway was a winding path longer than what is shown here, and there was also no roundabout. (00:06:04)
Continuity mistake: When Shadow King is saying Rogue will not dare attack him while he is possessing Storm's body, Storm's left earring has been drawn behind her earlobe. (00:11:27)
Continuity mistake: When Rogue is saying that Storm threatened to flood the hospital kitchen if they didn't release her, Storm's left hand, which is draped over her hip, is colored white. (00:03:13)
'Til Death Do Us Part: Part 2 - S2-E2
Continuity mistake: When Morph is remembering who Mr. Sinister is, the flashback shows Morph lying on the ground with his right side facing Mr. Sinister. However, the previous episode showed that Morph's left side was facing Mr. Sinister. Morph is also suddenly wearing a jacket in this flashback. (00:14:34)
'Til Death Do Us Part: Part 2 - S2-E2
Character mistake: In the establishing shot of the movie theater where the Friends of Humanity meeting is taking place, the word "Humanity" on the marquee is incorrectly spelled as "Humanty." (00:06:32)
'Til Death Do Us Part: Part 1 - S2-E1
Revealing mistake: After Morph laughs when the police have shot Storm out of the sky, there is a split-second flash of the establishing shot of the Veteran's Building Jubilee went to a little earlier in the episode. Note, this mistake may only occur on Disney+. (00:20:31)
'Til Death Do Us Part: Part 2 - S2-E2
Other mistake: When Mr. Sinister and the Nasty Boys are fleeing from the X-Men, their plane takes off a split-second after they have all disappeared into the treeline. (00:19:10)
Continuity mistake: When Pierre is telling the Assassins that they betrayed the Thieves, he raises his left arm and points his finger at them, and then lowers his arm back down. When the shot changes, his left arm is raised again. (00:15:00)
Revealing mistake: When Bella Donna is preparing to shoot a blast of energy at Rogue, her body passes through the left hand of the man on her left that was holding her back. Half of her cloak then disappears as she strides forward. (00:14:42)
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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