: Characters gain experience, level up, and earn skill points to unlock or enhance active and passive mutant powers.

The game's success led to the 2005 sequel, , which expanded the roster to include playable villains from the Brotherhood and introduced online multiplayer. This series eventually evolved into the broader Marvel: Ultimate Alliance franchise. X-Men Legends... 20 Years Later

: The narrative centers on the X-Men's struggle against Magneto’s Brotherhood and the anti-mutant Sentinels, eventually leading to a climactic showdown on Asteroid M. Gameplay Mechanics

: Players can execute "Team-up" attacks by chaining their powers together, such as combining Cyclops' optic blasts with Wolverine's physical strikes.

The game combines fast-paced beat-'em-up combat with deep RPG customization.