Using your fists, knife, or gun, you must use the elevators to travel between floors and wipe out terrorists that try to bring you down. Each weapon has its disadvantages. The gun, for example, will only have so many bullets per life, and the knife will decrease in strength with every use. During your mission, you will also earn experience points, and meet and free hostages along the way. These hostages will heal you, fix your knife, and give you a machine gun. Some floors end with you defeating a boss, while others end at elevators. Your must reach the top of the building where you will confront the leader.