Trivia: The show contained numerous references to the Terminator film series. Several episodes such as "Time Fugitives" and "One Man's Worth" (also "Days of Future Past," but that was based on a pre-Terminator comic) featured one or more characters traveling into the past to prevent an event that causes a dystopian future. The robots from Cable's future bear a resemblance to the T-800s. When Mr. Sinister's body is blown to bits in "Reunion, Part 2" it begins to reassemble itself exactly like the T-1000 when it was frozen and then blown to bits. Wolverine even refers to Bishop as Mr. Terminator in the episode "Days of Future Past, Part 1." Another Schwarzenegger movie, "Total Recall", is referenced in "Time Fugitives, Part 2" when Cable uses a hologram of himself in order to bait someone into shooting at him.
Time Fugitives: Part 1 - S2-E7
Trivia: War Machine (the supporting character from Iron Man) makes two brief cameo appearances in this episode. The first is in Cable's future after Cable tells his team that they aren't retreating. Whether or not the person inside the armor is James Rhodes or why he is a servant of Apocalypse is not explained. The second is when he is watching the Senate committee on TV along with G.W. Bridge and Nick Fury. (00:02:50)
The Phoenix Saga (1): Sacrifice - S3-E3
Trivia: The orange space suits that the X-Men wear more closely resemble those worn by Russian cosmonauts than the black and white space suits worn by American astronauts. This is likely the result of the animation company in the Philippines being given notes to draw the characters in space suits, but in their research probably came across the Russian design, and not knowing any better or investigating further, went with that style.
Trivia: George Buza, who voiced Beast, never watched any episodes of this show until 2019, more than 20 years after the show ended. He finally decided to watch them at the insistence of Cal Dodd, who voiced Wolverine, because Buza was scheduled to be a guest at his first comic con, and decided he needed to have knowledge of the show, knowing that fans at conventions would be asking him questions about it.
Trivia: Despite the character's current massive popularity, Deadpool only made three unofficial cameos on this show, as the character was not nearly as popular in the early 90s. Once as a mental projection during a psychic session between Professor X and Sabretooth in the season 1 episode "Deadly Reunions"; as an illusion created by the dark side of Professor X's consciousness in the season 3 episode "The Phoenix Saga Part 2: The Dark Shroud"; and as form that Morph took during a confrontation with Wolverine in the season 2 episode "Whatever It Takes." Deadpool was set to make his first official appearance in a television series in the second season of "Wolverine and the X-Men", but that show was canceled before this ever came to fruition.
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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