Other mistake: When Cyclops blasts Iceman with his optic beam, the image of Wolverine encased in ice remains on-screen, when it looks as if the shot was supposed to completely change to Iceman getting knocked back by the blast. (00:05:35)
The Dark Phoenix (2): The Inner Circle - S3-E12
Other mistake: When Wolverine lands on Leland with his claws extended, if you look closely you'll see that Wolverine's left hand ends up in Leland's chest area, yet Leland was not impaled by the claws like he should have been. (00:17:15)
Dark Phoenix (1): Dazzled - S3-E11
Other mistake: When Moira McTaggart asks Jean what happened to her, keep an eye on Banshee. His body slightly stretches horizontally for a split-second. (00:01:15)
The Phoenix Saga (3): Cry of the Banshee - S3-E5
Other mistake: When the text depicting the episode name appears on screen after the opening credits, it says "The Phoenix Saga Part 2, The Cry of the Banshee." It should read "The Phoenix Saga Part 3, The Cry of the Banshee." Note: this mistake may only apply to the DVD version of the episode. The episode that appears on Disney+ correctly depicts it as "Part III." (00:02:20)
The Phoenix Saga (4): The Starjammers - S3-E6
Other mistake: When the X-Men and Corsair encounter D'Ken in the hallway, D'Ken, Gladiator and Lilandra remain in the background while the X-Men and Corsair are wiped from the screen. It's as if this was meant to be a zoom in on D'Ken, Gladiator and Lilandra, but their size relative to the camera remained the same and the X-Men and Corsair are simply removed from view. (00:19:35)
The Phoenix Saga (4): The Starjammers - S3-E6
Other mistake: When Gambit is tossing playing cards in Lilandra's helmet, he is shown tossing four cards. All four cards are the exact same card (the ace of spades). (00:13:30)
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)
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)
'Til Death Do Us Part: Part 2 - S2-E2
Other mistake: The show establishes that Jubilee is Chinese-American, but after she accidentally blasts Wolverine, the way she pronounces "Sorry" is the way the word is typically pronounced by Canadians (most of the show's voice cast, including the actress who voiced Jubilee, are Canadian). (00:11:00)
Other mistake: When Magneto is watching the X-Men depart to rescue Senator Kelly, his cape can be seen swaying in the wind, but not his hair. (00:11:20)
Slave Island - S1-E7
Other mistake: When Storm sends the Genoshan prison guard flying into the Blob, he knocks the Blob over. The Blob's powers prevent him from being moved, hence why he is sometimes called the Immovable Blob. Other episodes demonstrated his ability to stand his ground against force, such as being punched by Rogue or being blasted by Cyclops' optical beam.
Night of the Sentinels: Part 2 - S1-E2
Other mistake: After Storm and Cyclops fly away from the barrage of Sentinels, one Sentinel is shown to have his right foot "floating" on top of the left foot of another Sentinel, almost as if their feet were occupying the same space. (00:11:25)
Other mistake: During a flashback, Rogue is shown absorbing Pyro's mutant power and then creating fire out of thin air. However, Pyro does not have the ability to create fire, he can only control it. That's why he wears a flamethrower on the back of each hand.
Savage Land, Strange Heart (2) - S3-E9
Other mistake: When Rogue tells Beast that the word "Zaladane" kept popping in and out of her head when she and Sauron made physical contact, a border roughly in the shape of the letter "D" appears around her mouth. (00:08:08)
The Phoenix Saga (4): The Starjammers - S3-E6
Other mistake: When D'Ken is saying "Destroy them all," he is speaking with a German accent. (00:17:09)
The Phoenix Saga (3): Cry of the Banshee - S3-E5
Other mistake: When Xavier is telling Moira about how he and Lilandra were attacked, Moira dismisses his claim, reasoning that he came to her for help because he could no longer trust his own mind, and that no-one else had been in his room. She witnessed him flying out of a window, and he's a paraplegic. Unless she thinks he somehow catapulted himself out the window, she shouldn't have been so dismissive of his claim. Not to mention the damage to the room, including the bed being thrown against the TV. (00:05:21)
The Phoenix Saga (1): Sacrifice - S3-E3
Other mistake: When Dr. Corbeau opens the door to the locker room, Cyclops, Jean Grey and Wolverine are in his direct line of sight. Despite this, it isn't until he takes several steps into the room that he realises they aren't his shuttle crew. (00:08:35)
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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