You crash-land alone on an alien world. Find your downed ship by following its emergency beacon, build a fort around it out of walls, blast doors and automated laser turrets, then head out into the wilds to salvage seven scattered ship parts and carry them home one at a time while alien bugs hunt you.
Drag to walk, run, backpedal and turn. Tap to fire your shoulder laser cannon. Switch to build mode to place walls that snap together into a sealed perimeter, swing them into position, and mount turrets that track and shoot on their own. Grenades clear swarms. Survive long enough and the toughest monsters appear — including the brute, a gorilla-sized tank that takes eighteen hits to drop.