Lo, I’ve been devoting some thought to this while I have been at work, and I’ve come to conclusion that we’re all overlooking something.
What are the X-Men’s relative positions at the beginning of the fight?
If the characters are fairly far apart, say spaced evenly about the danger room’s perimeter, then Jean Grey, Cyclops, Iceman, and Storm are the favorites because their powers can work at a distance. Cyclops is my personal favorite because it wouldn’t take him much time to fill the room with a wide-angle beam strong enough to kill anything human. That takes out most of the X-Men. If Cyclops’ beam is strong enough to destroy a mountain, then he can take out Colossus, Iceman and Rogue (from what I remember, she isn’t as invulnerable as Superman). I agree with Fenris that Jean Grey can do the stunt he described above, but I think it will take her at least a few seconds against people trained to resist mental attacks. As I recall, even Saturn Girl needed a couple of seconds to take out Mon-El and Ultra Boy while they were under Universo’s control.
If the X-Men are placed close to one another for immediate melee, then my favorites would be Wolverine, Colossus, Rogue, and the Beast. If Gambit is on the edges and hangs back to take on the winners, he might pull it off. I think Jean Grey is at a disadvantage is such a scenario because Hank McCoy is bright enough to launch a full-strength flying kick at her head and putting him into a coma isn’t going to alter the laws of physics.
Personally, I think a much more interesting scenario would be to scatter the X-Men thoughout the mansion and have them seek one another out. In this scenario, my favorites would be Wolverine (as the Phoenix saga relates, he is very stealthy, and Logan probably has some experience in guerilla tactics), Jean Grey (she should be able to sense her opponents’ position) and the Beast (y’all are underestimating Hank McCoy. He is fast and strong enough to take out in hand-to-hand combat all X-Men but Colossus and Rogue, and he is bright enough to whip up a weapon against those two or else manuever them into the Danger Room and use that against them.)
Put the X-Man outdoors, say on a deserted island, and then my favorite would be Storm. If she gains the air, then only Rogue has a prayer of stopping Ororo.
Also, I think any X-Man has a chance of winning a fight. I can see the Angel (one of the most useless heroes ever) winning if the fight is in the danger room and he flaps to the ceiling to wait it out. In this scenario, say Cyclops is the penultimate X-Man. Warren can swoop down immediately after Cyclops finishes off his last opponent, grap Scott from behind, and take him up to the ceiling. Even an accomplished martial arts artist is going to be stunned from a long fall onto concrete or metal. Warran can repeat the process until Cyclops is dead or too stunned to offer resistance to the Istanbul twist.
Shouldn’t my employers be grateful?