X-Men Legends is a real-time role-playing game where players put together their own team of X-Men heroes to combat such legendary foes as the Morlocks, Brotherhood of Mutants, and Sentinels. In true role-playing game fashion, players control their group of X-Men characters to take advantage of each individual's special powers and abilities while in combat. As each character becomes more experienced in battle, his or her powers will grow over time and new fighting moves become available to help the character develop into a more formidable opponent.

Players will assemble their party from a lineup of more than 15 characters, including popular favorites Wolverine, Cyclops, Storm, Nightcrawler, Colossus, Gambit, and Beast. Certain locales may require stealth to avoid alarm systems or traps, making Wolverine or Nightcrawler more valuable team members, while multiple enemies may be more quickly dealt with using the crushing power of Colossus or the Beast. Players will have to carefully weigh the pros and cons of each superhero before forming the party and beginning a mission.

Once a mission begins, players can switch control between the mutants at any time and can even implement combo moves between specific characters, such as Wolverine's and Colossus' "fastball special" maneuver, which has Colossus picking up Wolverine and tossing him at a foe to dole out heavy damage. Up to four players can join in the adventuring together, working as a team or honing their superhero skills from within the Danger Room training ground. Man of Action, a four-man production company of veteran comic book authors, wrote the game's storyline.