After a nuclear war, humanity's livestock has been extinct and the survivors travel the galaxy in search for new sources of protein. Players take control of an alien that has been captured by one of the human ships. Seen from a side-view perspective, the alien must find it's way through the ship, going through color-coded transporters, jumping over and dodging obstacles and blasting numerous enemies. Sometimes, defeated enemies drop items that increase firepower, replenish health or reverse the controls. Fellow prisoners can be rescued to gain extra lives. The main goal however, is to find a bomb that has been planted on the ship before the timer reaches zero. Once this is achieved, the alien can exit the ship and try to make its way to the inside of his home planet where an escape pod is hidden.