The superhero universe is embroiled in civil war, and it's time for players to choose sides in Marvel Ultimate Alliance 2. The game is a mission-driven action-adventure with a focus on small-squad combat, viewed from an isometric perspective. As in Marvel's earlier 3D action games (such as titles in the X-Men Legends series, as well as the original Marvel: Ultimate Alliance), role-playing aspects also influence the adventure, with gamers choosing which heroes to control, and how to improve their various superpowers and abilities as they gain experience by defeating enemies and accomplishing goals.<br><br>In most scenarios, a team of four Marvel heroes battles a path through areas teeming with high-tech defenses, heavily armed thugs, and rival superhero and supervillian enemies. Players can switch control between the characters, while the computer takes control of additional teammates. Co-operative multiplayer modes for up to four are available, both online and for same-screen players. While all the heroes and villains can perform basic maneuvers such as leaps and melee attacks, each also has a distinct superpower. Over two dozen heroes and villains are available for play, and the special powers of any two super-beings can be combined into a new, even more powerful "fusion" ability. A team with a good mix of special abilities is better prepared for the diverse dangers and challenges that wait in each mission.<br><br>The story of the Ultimate Alliance 2 is taken from the Civil War saga, the major crossover event that was first revealed in the pages of multiple Marvel comics in 2006 and early 2007. The U.S. government is calling on all super-powered humans to reveal themselves and register with an official agency, for the safety and protection of the population at large. Heroes and villains now reevaluate past loyalties and regroup according to their stance toward this conflict, which pits the security of the people against the liberties of the individual.