In a solar system on one of the satellites of the unknown planet once upon a boy Sponge and Leroy robot. But one day, the invaders from the Earth decided to take possession of their home, and began the attack with stones, namely the fact that so many in space. You have to do as a sponge to fire by attacking robot Leroy. The first levels are not difficult, the rest do you need to modify your gun to counter the attack.