For many years a war has ensued between the Allied Nations and the Volgans. You play the role of Commander John Stryker, commissioned by the Allied Nations to undertake a perilous mission that, if successful, will give the Allies a fundamental strategic advantage over the warmongering Volgans.

Your task is to locate and seize the Volgan's latest weapon: a new spacecraft (codenamed Z11) which is equipped with the revolutionary matter/anti-matter warp drive facility. You have landed on the mysterious planet Volga, and you must now penetrate the Volgans' underground defence systems, find the spacecraft and requisition it.

You can jump, run, kneel, crawl, climb up and down ropes, ascend and descend by using lifts, fire your laser blaster, drop mines, and pick up any objects that you find. You can also access information via your wrist terminal computer, and you can fly for short distances by using a jet-pack.

There are many objects scattered around that you can collect and use. To pick up an object simply run over it.

In order to be able to requisition the Volgan's Z11 spacecraft, you must collect four sets of plutonium rods (to power the craft) and a navigation ROM which is required by the spacecraft's computer.

As you descend below the planetary surface, you will pass through four different zones of Volgan activity:-

• The Surface Defence,
• The Ancient Shrine,
• The Crew's Quarters,
• The Missile Factory.

Each zone has three sub-levels called sectors. These are simply numbered 1 to 3. You start at "Surface Defence - sector 1" and descend through sectors 2 and 3, and then on to the next zone.

Moving from one sector to another is accomplished by entering a lift and pressing the appropriate key to ascend or descend. However, you need one security password in order to ascend or descend by 1 sector. Volgan soldiers are strategically positioned defending each sector. As you descend, the Volgan soldiers become more powerful: they inflict more damage and possess a higher armour-stress factor - you will need to shoot them several times to kill them.

You can kill a Volgan soldier in several ways:-

1. by shooting him,
2. by dropping a mine in his path (you can leave the mine and when the Volgan runs into it you will hear it explode no matter where you are in the sector),
3. by jumping onto a Volgan soldier (not always effective),
4. by crashing into a running Volgan soldier, or
5. by tricking two Volgans into shooting each other (while you jump out of the way).

To look at the micro-film maps, you must have first picked up a microfilm cassette - you'll find one in the Surface Defence zone. Press "A" to access the wrist terminal computer and then press "M" to view a map of the current sector. The map can be scrolled to display the entire sector. The positions of the Volgan soldiers are also shown.

When you walk into a jet-pack, you will be placed onto the jet-pack: you can then thrust left and right, and by pressing RETURN you can thrust upwards. Release RETURN and you float downwards. The jet-pack has its own built-in blaster which does not drain power from your own blaster energy. The jet-pack also has its own computer which is accessed by pressing "J" - it shows the current blaster energy and the remaining jet pack fuel. The jet-pack can be refuelled by picking up a fuel canister.

Most of the objects that you will discover are required for one purpose or another. But the mystery crates are particularly useful. When you pick one up all of its contents are assumed to have been picked up. The contents are usually several security passcards and/or energy cells. Springs are also extremely useful: they allow you to jump higher than normal - but picking up any other object immediately cancels the effects of the spring - so plan your movements carefully.

You can jump immediately to the start of zone 2 or zone 3 if you have reached it in a previous game. To do so, press "J" on the introductory screen and you will start at zone 2 (or zone 3 if you have reached that far previously). Your status (lives, energy, equipment, etc) will be set exactly as it was when you first entered that zone.

However, to requisition the Volgan's Z11 spacecraft and receive the congratulatory message you must complete the entire game without the JUMP option.

Press the "A" key to access your wrist terminal computer. The computer screen will show you important information. The current zone is displayed (Surface Defence, Ancient Shrine, Crew's Quarters or Missile Factory) and under this is shown the sector within that zone (1, 2 or 3). Also displayed is your score, the number of lives remaining, and the number of mines which you are currently carrying. Each time you enter a sector after using a lift you will automatically be given six mines in exchange for your security passcard.

The suit energy and blaster energy are shown graphically as energy bars. Your suit energy is decreased each time you are shot by a Volgan soldier and if your suit energy reaches zero, you will be unable to fire your blaster until you have recharged it. To recharge either suit or blaster energy you must first pick up an energy cell, then access your wrist terminal computer and press "S" to recharge your suit energy or "B" to recharge your blaster energy.

Finally, the number of spare security passcards and energy cells which you are carrying is displayed.

Z - Run Left, X - Run Right, * - Fire Laser Blaster, RETURN - Jump
+ - Climb Rope/Ascend in lift, > - Climb down rope/descend in lift/kneel/crawl
D - Drop a mine, A - Access wrist terminal computer
J - Access jet-pack computer, O - Leave jet-pack, Q - Lose a life
ESCAPE - Restart game

(Note: Stryker cannot crawl off the screen. To move to the next screen, he must stand up and run across)

1 - Sound off, 2 - Sound on, J - Depth Jump (if offered)

M - Display micro-film maps and enemy positions
S - Recharge suit energy, B - Recharge blaster energy
SPACE . Exit from wrist terminal computer