Single Player, HD (High Definition) Fight your way through room after mutant-filled room in a quest to save the human race. Collect weapon upgrades, earn bonuses for clearing a room quickly, and don't forget to use the architectural obstacles to your advantage. The difficulty level rises each time you progress. Survive, and you could earn the elusive Black Belt. There are no refunds for this item. For more information, see www.xbox.com/live/accounts.