This is a challenging, old-school, retro, side-scrolling shooter. The player must defend the base against 28 waves of alien attackers. There are also 10 bonus twin-stick shooter levels, where the player controls a security robot defending the base from enemies tunneling in from below.

Aliens are attacking an isolated base on a remote planet from the air and from underground. The only hope in defending the base is an artificial intelligent spacecraft, called Defensa, and a lone security bot, named Hitch. These two defenders must work with their resources and repel the assault on the base.