Just when you thought it was safe to holster your laser, Andrew Pillige reveals a new threat to mankind

Pick up your laser and fasten your seatbelt for an ultra-fast ride in this brilliant game of galatic conquest.

For a long time the planetary system of Sirius VII has been used as a storage facility for cosmic battle weaspons for use against the Jelquon invaders, but the war against the marauding hordes has not been going too well recently.

The aliens have found ways of using captured weapons against the interplanetary defence force, and civilisation as we know it is threatened with annihilation once more.

One night you are left to watch over the depot of picowave laser generators and pion energy storage drums.

At first everything seems peaceful, your eyelids are beginning to sag when suddenly, thousands of Jelquon marsh creepers drop out of hyperspace to try to steal the laser guns. With lightning reflexes you leap to the controls of your laser generator and start to defend the stores against the relentless waves of hideous beings.

Fortunately they have to get through the storage drums to reach the lasers, but how long can you hold them off?

After four waves of attackers have been destroyed, reinforcements will arrive in the form of another laser.

The action is fast and furious so you'll have to work quickly. The future of mankind rests in your hands.

COSMIC GUERRILLAS is without doubt one of the fastest shoot-'em'up games seen on the Electron.

As is usual with listings that contain machine code, it is essential to save the program before running it.

A typical error when entering the listing could cause a crash (which won't do any harm, but you'll have to switch off for a second or two).

NEWMARKET is a two player micro version of the popular card game of the same name, featuring superb graphics and a challenging opponent - the Electron.

The rules are very simple, made even easier because the program has been written to do all of the laborious work for you.

The object of the game is for one of the two players - you or your Electron - to discard all of the cards in their possession. This must be achieved in the following manner.

Initially, three hands of seventeen cards are dealt, the Electron's face down in a pile, yours laid out on the screen. The remaining hand of 18 cards, known as the dead pack, is kept in case you wish to change the one you have been dealt.

When prompted, you play your lowest red card by inputting the number displayed directly underneath it. You may pass if you wish by pressing RETURN. Aces are regarded as low.

If you hold the next consecutive card of the same suit, it is removed automatically. If you haven't got it in your hand, control will pass back to the Electron.

If it cannot follow, control returns to you. You must then play your lowest black card. This process is repeated until either player has discarded all seventeen cards, thus producing a winner.

When the game has finished, press the SPACE bar for a new one or Q to exit the program.

After entering the listing it is essential to save it before you run it, even on tape based systems, since part of the program is deleted when the program is run for the first time.

THE GOLDEN CROWN is a short program which demonstrates how to write intriguing chaining puzzles in your own home-grown adventure games.

It is in fact a complete adventure game in its own right and can be played as such, though it would be better incorporated within a much larger program. Seasoned adventurers will find the solution fairly straightforward and should not take too long to work it out, but novices may find it an interesting and stimulating brain-teaser.

Chaining puzzles are quite common in text and arcade adventures and involve a central problem whose solution requires several logical steps which must be performed in a set sequence.

For instance, suppose you want to have a drink from a well, but can't reach the water.

A possible solution to this problem may be to dig for gold dust in the mountains nearby, take it to town and exchange it for money in order to buy a rope and bucket. The bucket can be tied to the tope and lowered down into the well to fetch the water. Now you can have a drink.

So you have a series or chain of linked puzzles which must be solved in order: You need a bucket to get the water and rope to lower it down the well, but require money to buy them both and some valuable object to trade to get the money.,

There are just sixteen separate locations in THE GOLDEN CROWN and the adventure is based in the far-away land of Karnia. The King's crown has been stolen by one of his enemies and it is your task to recover it.

In return for this favour, the King will knight you and great wealth will be yours.

The command parser, although rudimentary, will understand instructions like: NORTH, SOUTH, EAST, WEST, TAKE, UNLOCK, KILL, EXAMINE and so on. Abbreviations may confuse it so don't try any. The vocabulary of words understood by the program is stored in v$.

The location descriptions are in r$(), the exits in e$(), objects in ob() and messages in m$().

When an object is taken its location number stored in L() is set to 16. If it needs to be removed from the game it is set to 16. If it needs to be removed from the game it is set to 32. Your current location is held in p.

That just about rounds up this adventure programming series. You should now have enough information and techniques at your fingertips to start writing your own adventures - so get cracking.