It is your task to destroy the evil race of Zerans, who live on the volcanic planet of Zeras. To do this you must make your way through an underground metropolis to the depths of the city, where you will find a volcanic plug. If you can plant your plasma bomb there, you will blow up the planet. But you must make your escape before the city fills up with lava. Okay?
The Zerans resemble purplish coloured amoebas and they scutter round the city complex in company with their much bigger staves. Often the Zerans will ignore you, but they may try to crush you. 'You ' resemble a little black spider.
There are five skill levels and depending on which one you select there are between 3 and 15 levels to the city. The display shows you only a tiny part of the whole complex (of one floor). There is a map at the top right hand corner of the entire floor you are on and looking at it gives you a headache! It's huge.
Your protection is a suit or armour which wears down as the Zerans fire at you. When it's gone the two other systems, power and bio system, become vulnerable and you die if they fail. Your blaster has plenty of charge, but that too runs down with use. These four are shown as falling bar codes at the bottom of the screen. Here and there in the maze you will come across various objects like tool repair kits and spare oxygen, but you must be quick because a Zeran will take them if he gets there first.
To go to another floor you must find the lifts, which are going up and down all the while. When you enter one (wait for it to arrive at your floor) you can activate it but you won't know whether it's going up or down, only the indicator at the left of screen tells you this. Entering an up lift on the top floor replenishes all your armour and power. Lifts only connect between 2 floors, otherwise it would be too easy.