This is a third-person shooter in which players assume the role of a guerilla soldier who engages in combat missions against aliens and an apocalyptic cult on Mars. Players use plasma guns, rocket launchers, machine-gun turrets, and explosives to shoot and kill alien creatures and human soldiers. Battles are highlighted by realistic gunfire, large explosions, and cries of pain from injured characters. Blood-splatter effects frequently occur when enemies are hit; some enemies explode into pieces when killed—body parts and large bloodstains are depicted on the ground. Players also have the ability to inflict damage on enemies that have been killed. The words "f**k" and "sh*t" can be heard in the dialogue.