A DESOLATE asteroid houses an advanced anti-matter conversion plant, set up by an outlying system of the Terra Federation.
A group of aliens has penetrated its defences and has threatened to destroy the plant, turning it into a black hole which would suck thousands of inhabited planets into its colourless void. Your mission is to disable the plant before it achieves critical mass.
At the start of the game a 3D representation of a desert world is panned across the main display window until the dome-shaped hover pod launcher comes into view.
Using joystick or keyboard you must orientate the pod and then press the accelerator. The joystick is easier to use as a simple one way movement is enough to control the craft.
There are five zones through which you must travel. In the first zone you will encounter giant worms and dust balls. In the second zone you will have to contend with alien hover pods as well.
Your pod remains intact while its shield has enough power, but bumping into obstacles and being hit drains its resources. When your shields drop the pod will implode, and you must follow directions to the nearest pod launcher to collect another craft.
If you manage to get into the final zone the walls of the power plant soon appear. To enter you must disable the protective wall and destroy the source of the energy beam.
The desert world portrayed in Critical Mass bears a remarkable similarity to Frank Herbert's Dune. Even the hover pods looked like the winged ornithopters portrayed in the film.
Joystick: Kempston, Sinclair, Downsway, Protek