Edi Gathegi (Twilight) has been cast as the mutant "Darwin" in Matthew Vaughn's X-Men: First Class.  The character's mutant ability is "reactive evolution", which means he can instantly adapt to any environment.  So if he's underwater, he'll grow gills.  If he's in a fire, his skin will become flame-retardant.  If he's at a Nickelback concert, he'll remove his ability to hear.  Gathegi recently wrapped filming on the Paul Johansson-directed adaptation of the Ayn Rand novel Atlas Shrugged.

Deadline also reports that Aaron Johnson is still rumored to play the role of Cyclops although EW says Johnson's he's not playing Cyclops or any other role in the movie.  EW also said that Fox is releasing the names of characters who aren't in the film so that it will be a surprise for fans when it's announced which roles the actors are really playing.  Hit the jump for more confirmed and rumored casting.  X-Men: First Class is set to open on June 3, 2011.

Here's the confirmed casting:

And as for rumored casting:

The characters “Multiple Man” and “Willow” are also rumored to be in the film.  If there are misdirects among the roles, I would believe these would fall into that category.  It’s either that or (hopefully) they’re background characters like Kitty Pride/Shadowcat in the first two X-Men movies.

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