The defeat of the Covenant in the first Halo game was only a temporary victory, as the alien attackers have renewed their mission to wipe out all of humanity. Despite the human military force''s and Master Chief''s efforts, the Covenant have breeched the Earth''s defenses and have left its inhabitants in a dismal situation. In the midst of desperation, players assume the role of Master Chief and lead the resistance against the Covenant to save the people of Earth from a gruesome demise. The long-awaited PC version of Bungie''s FPS, Halo 2 offers the full single-player campaign and multiplayer maps of the original Xbox version, with the addition of the content in the Multiplayer Map Pack as well as a tool for building and customizing levels. The game requires Windows Vista.