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.

The scenery consists of earth, rocks, and various wall formations, but
occasionally you will discover supplies left by space probes. These
may take the form of bomb craters, fuel drums or even spare dozers,
all these supplies as well as your Astra-Dozer are fitted with
anti-grav fields as they are not affected by gravity. Good luck.