* HeyItsThatVoice:
** Creator/PatrickStewart reprises his role from the [[Film/{{X-Men}} movies]] as Professor Xavier.
** Likewise, RobinAtkinDownes reprises his role from ''XMenNextDimension'' as Pyro and takes on the role of Cyclops in the first game (while absent in the second game, he'd later reprise the role of Cyclops in the first ''MarvelUltimateAlliance'' game).
** This series would also be the first time Creator/SteveBlum and Peter Lurie voiced their respective roles of {{Wolverine}} and Sabretooth, with both reprising their roles in ''MarvelUltimateAlliance'', ''WolverineAndTheXMen'' and ''WesternAnimation/{{Ultimate Spider-Man}}'' and Steve as Wolverine [[WesternAnimation/AvengersEarthsMightiestHeroes a]] [[HulkVS lot]] [[SpiderManWebOfShadows of]] [[TheSuperHeroSquadShow times]] [[MarvelVsCapcom3 since]]. Steve also voiced Omega Red in the second game and Peter voiced Avalanche in the first game, and [[AgeOfApocalypse Holocaust]] and [[TheOtherDarrin Blob]] in the second one.
** Creator/CreeSummer is Magma; while she herself wasn't in any prior incarnations of X-Men, her father, Don Francks, voiced Sabretooth in the 90s ''WesternAnimation/{{X-Men}}'' animated series.
** JohnDiMaggio is Juggernaut.
** Creator/JenniferHale is Scarlet Witch and the Stepford Cuckoos.
** Creator/JoshKeaton is Cyclops [[TheOtherDarrin in the second game]].
** Creator/EdwardAsner is Healer.
** Lou Diamond Phillips ([[StandAndDeliver Angel Guzman]]) is Forge.
** Creator/TaraStrong is Blink.
** TonyJay is Magneto in the first game.
*** Richard Green ([[WesternAnimation/TheBatman Hugo Strange]], [[WesternAnimation/TransformersPrime Skyquake]]) is Magneto in [[TheOtherDarrin in the second game]].
** John Kassir ([[TalesFromTheCrypt The Crpyt Keeper]]) is SelfDemonstrating/{{Deadpool}}, Pyro ([[TheOtherDarrin in the second game]]), and Sauron.
** Creator/KharyPayton is Bishop and Nick Fury.
** JamesArnoldTaylor is Iceman [[TheOtherDarrin in the second game]].
** Music/GreyDeLisle is Mystique.
** Dawnn Lewis ([[ADifferentWorld Jaleesa Vinson-Taylor]], [[HanginWithMrCooper Robin Dumars]], [[WesternAnimation/SpiderManTheAnimatedSeries Terri Lee]]) is Storm [[TheOtherDarrin in the second game]].
** Danica [=McKellar=] ([[TheWonderYears Winnie Cooper]], [[StaticShock Frieda Goren]], [[WesternAnimation/YoungJustice Miss Martian]]) is Jubilee.
** Earl Boen ([[TheTerminator Dr. Silberman]], [[MonkeyIsland the ghost pirate LeChuck]]) is Colossus in the first game.
*** Jim Ward ([[DannyPhantom Bertrand]], [[WolverineAndTheXMen another Professor X]], ''Radio/TheStephanieMillerShow'', [[WesternAnimation/AvengersEarthsMightiestHeroes Baron Strucker]]) is Colossus [[TheOtherDarrin in the second game]] and [[AlphaFlight Guardian]].
** Creator/DeeBradleyBaker is Nightcrawler and Multiple Man.
** Richard [=McGonagle=] ([[WesternAnimation/{{Ben10}} Four-Arms]], [[WesternAnimation/Ben10AlienForce some of the Highbreed]], [[WesternAnimation/StarWarsCloneWars General Grievous]]) is Apocalypse in the second game.
** Alastair Duncan ([[WesternAnimation/TheBatman Alfred Pennyworth]], [[LegacyOfKain Mortanius]], [[Franchise/MassEffect Councilor Sparatus]]) is Bastion.
** Masasa Moyo ([[CelebrityDeathmatch Tally Wong]], [[JadeEmpire Silk Fox]], [[JediStarfighter Adi Gallia]]) is Psylocke in the first game and Shanna The She-Devil in the second.
** Dorian Harewood ([[WesternAnimation/IronMan War Machine]], [[WesternAnimation/MegasXLR Ender]], [[WesternAnimation/TheBatman Martian Manhunter]]) is the Shadow King.
** Armin Shimerman ([[WesternAnimation/EvilConCarne General Skarr]], [[Series/StarTrekDeepSpaceNine Quark]], [[Series/BuffyTheVampireSlayer Principal Snyder]], [[VideoGame/BioShock1 Andrew Ryan]]) is Toad.
** Catherine Taber ([[VideoGame/KnightsOfTheOldRepublic Mission Vao]], [[WesternAnimation/StarWarsTheCloneWars Padmé]], [[VideoGame/TheForceUnleashed Leia]], [[VideoGame/FinalFantasyXII Penelo]]) is Rogue in the second game.
** Keith Ferguson ([[Franchise/KingdomHearts Marluxia]]) is Grizzly in the second game.
** Kim Mai Guest ([[VideoGame/MetalGearSolid Mei Ling]], [[VideoGame/DeadRising Isabela Keyes]]) is Lady Deathstrike in the second game.
** QuintonFlynn is Banshee and Abyss.
** DwightSchultz is Garokk and the Living Monolith.
** DaveWittenberg is Archangel.
** Daniel Riordan ([[Anime/TransformersRobotsInDisguise Megatron]]) is Mr. Sinister and Stryfe.