In the year 3080 the Galactic Lifeform Commission decided to start work on an interstellar by-pass. It is your mission to clear the 30 different star systems and planets of all hostile habitation. You control a limited number of Astra-Dozers and must wipe out all Circsaws and Trigons. The Conenabs need not be eliminated and are mortal enemies of the Circsaws so this can be used to your advantage.