|The aim is to blow up all the enemy tanks. Simple enough...|
At the top of the screen is the radar display, showing where the enemy tanks appear. Taking up the rest of the screen is the view through your tank's gun turret. The various pyramids, cubes, prisms and so on scattered around the landscape don't harm you but do block your movement and firing.
The damage is done by four different type of tank, as well as flying saucers and missiles.
You are of course equipped with a cannon to destroy them, but you can only fire one shot at a time - if you miss, you must wait for your failed shot to vanish over the horizon before you can fire again. This means that accurate firing is essential...