The game has the player managing up to two five-men squads on missions against alien creatures aboard derelict starships called Space Hulks. Tutorials, stand-alones and a campaign make up the 50 missions, which include exterminations, object retrievals, and rearguard actions. Briefings on the background and objectives, along with a small preview map are given before missions. The player can customise the squads' armaments with weapons such as close range Lightning Claws and devastating long range Assault Cannons for certain campaign missions. Completing a campaign mission gains experience for the squad, allowing them to shoot and fight better on their own in future missions.