Cyclops plays a human cleric and never admits that he wanted to play a paladin but never managed to roll the stats needed back when Beast used to run AD&D and now he's just sort of settled into the role.
Colossus has been playing the same paladin since like the first time they met the Shi'ar and it secretly kills Cyclops because he makes it look really fun. Also Peter draws his character and cosplays his character and people give him his-character-related gifts for his birthday.
Kitty Pryde plays a halfling ranger or druid, just whatever gets her the animal companion fastest in that system, ok?
Storm wouldn't play for like years but then during the Blue-Team/Gold-Team era she was reconnecting with a lot of things and shyly was like "Hey can I play?" and now has this sorceress she is SUUUUPER protective of. Black Panther was baffled at first but has played a few sessions because people don't say no to Storm and now he's like one of those Batman tactical-thief types p.s. also never say "Batman" around T'Challa he will just excuse himself because he'd love to keep playing but there's matters of state, peace out mutants, enjoy your game. Storm would never roll her eyes in mixed company but she does kind of look briefly up at the ceiling when this happens and says it's ok she'll catch up with him later.
Psylocke plays an assassin and, yeah, seems to be working out some issues.
Iceman wants to play Vampire but plays D&D because that's ok, sure. Halfling fighter.
Cannonball plays a human fighter named Arthinius.
Jubilee plays that kind of thief that likes to backstab but is always forgetting to actually sneak first and is the kind of player that is the best reason they called it "rogue" in later editions but the X-Men don't use that term even when they play 5e (which Havok really wanted to try) because it would be confusing.
Illyana Rasputin would have been told by Colossus about the battle princess class because Colossus lurks OSR blogs and she really kind of wants to play one and the DM will let her but plays a tiefling wizard out of this kind of scary sense of hard-bitten Russian realism.
Havok uncomplicatedly plays an elf ranger and loves it. He is always texting like "When are we playing, guys?""Are we playing this week?""Are we going to that Con? It'd be funny we could cosplay as ourselves, you guys, wouldn't that be funny?". Sometimes Polaris comes along but nobody can remember where she left her character sheet so they keep having to make a new character for her every time.
Warlock wanted to play a lantern. In the beginning people tried to explain that equipment was a separate section but then they were like fuck it, sure guy, you're a lantern. He died and his new character is High Hard Boots.
Dazzler plays a half-elf multiclass fighter/wizard and does that thing where she completely goes off-goal and starts improvising intense motivations for her character but people are like actually this makes the game more fun, I'll roll with it.
"Hey Longshot, we're playing D&D!"
"Really??? I was going to go just to the pet store and watch frogs jump. But that sounds fun! Who do I get to play?"
"We still have that gnome monk you made."
"Oh, right yeah. Where are we?"
"Well when we left off you were all deep deep inside Demogorgon's palace and then you hear a rumbling from every direction...who's rolling initiative for your side?"
(all the players in unison) "LONGSHOT!"
Rogue plays an elf barbarian named Shugah Pie and rolls 20s, bitchessss.
Gambit has never been invited to play.
Cable played a half-orc cleric until 4e came out and then was all over the warlord (and all over 4e, Cable loves 4e with a blind and jealous ardor) and Beast makes him a little warlord hack for whatever system they're using. Cable is deeply touched by this but there is absolutely no way anyone would ever find that out, even telepaths. But Beast fucking knows.
Madrox will play anything. Well, some of him will.
Banshee DMs because he has a lot of time on his hands.
Beast DMs a lot, too, but when he isn't DMing he is always down to play and plays a thief with a high charisma and is basically the team leader in D&D.
Angel plays an elf fighter that is exactly like the Peter Jackson Legolas, including intermittent bits of the sort of moody Dark Legolas you see in the Hobbit movies.
Legion only wants to DM and only wants to run Carcosa but....is actually kind of good at it.
Magneto actually secretly only ever turns good because he likes DMing and seriously Blob and Pyro and Mystique are not playing D&D with anyone. Toad wants to but has never told anyone. He plays boardgames with Martin Prince from the Simpsons sometimes at the rec center but only when they can find something that's 2-player.
Sunspot plays a barbarian.
Wolverine would not play a barbarian. He just plays a dwarf fighter and he has a sense of humor about it because he used to drink with Fritz Leiber. Or at least the Wolverine I know. Fuck Hugh Jackman.
Nightcrawler has a good sense of humor but no sense of irony so he doesn't play a drow thief he plays a human ranger who is baaaasically Robin Hood. He's not minmaxed or anything but you always know everybody's making it out alive if Nightcrawler's playing.
Wolfsbane thinks D&D is devil sorcery at first but then got into and she's an elf druid. Kitty has to remind her what her spells are.
Professor X doesn't DM for the team anymore, the Starjammers and Lilandra made fun of him for it and he never quite got over it. He secretly sneaks off and plays Rolemaster with Reed Richards and Dr Strange though.
Fantomex is a savage minmaxer who plays whatever the most exploitable class is in whatever system but is actually not a dick or a spotlight hog about it to other players. Quentin Quire, though, do not get me started.
Deadpool shows up once in a while and says "Hey guys I can totally run Castle Greyhawk? Rat On A Stick?" His real passion is Paranoia though. Obviously.
Jean Grey doesn't play but is super-supportive of other people in the mansion playing and kind of envies that they could just be that creative and unselfconscious and instead locks herself in her room and masturbates while thinking about plane crashes.
The first time Emma Frost played it was just because she knew Jean Grey never played even though Cyclops was super into it but then she did actually herself get super into it but pretends not to be--she plays a dark elf cleric of some increasingly terrifying god.
Doug Ramsey is a fucking bard.