Spaceman vs. Monsters is a physics game in which you play as a spaceman. Your task is to eliminate the nasty aliens in each level without killing members of your crew. To help you accomplish this task, you will be given various items, such as knives, guns, jetpacks, and teleportation devices. You can eliminate the aliens by killing them with your weapons, blowing them up with explosives in the level, or causing them to fall off the stage.