Survive the onslaught of fifteen enemy types utilizing four contrivances, each with their own weapon compatibilities. You salvage scrap parts by destroying enemies, which are used to upgrade your contrivances, projectiles, and bunker.
Take control of 16 different units and 15 different turrets to defend your base and destroy your enemy. You start at the cavern man's age, then evolve. There is a total of 5 ages each with its units and turrets.