X-Men Legends II contains expanded versions of the gameplay features from the original X-Men Legends, with several notable additions:
* Online multiplayer modes.
* New characters are playable, including characters from the X-Men and the Brotherhood.
* New powers and abilities are available for all characters, and the player can switch between more than 4 mutant powers at once.
* After beating the game, the player could start a new game with their old stats.
Several characters from the first X-Men Legends were dropped from the roster of playable characters in the sequel: Jubilee, Magma (despite her being the main character of the first game), and Psylocke do not appear in X-Men Legends II, and Beast and Emma Frost appear but are not playable. Avalanche, a boss from the first game, also did not make an appearance.
