Topologika, the Peterborough software house, prides itself on producing British adventure games. Countdown To Doom, a text-only adventure which was first released by Acornsoft, could hardly be set further away from the land of Stilton and budding British businesses...

Travelling through space on a routine mission you're in orbit around the long-deserted planet of Doom, blissfully unaware of its efficient automatic defence system. Moments later your craft crash-lands on the inhospitable planet surface. Shaken, but otherwise unhurt, you examine the wreckage and realise that unless you can locate the necessary parts, collecting as much bonus treasure as you can in the process, your ship will corrode away in a mere 4/10 time units.

At close quarters the planet looks even more forbidding than it did from the sky. Its hostile terrain is characterised by extreme changes of climate; murky swamps border leafy jungles, mountain paths lead up to icy glaciers and down into the exhausting heat of a sandy, disorientating desert. The locations are extensive, atmospherically described and, for the most part, extremely hazardous. Striding boldly into the unknown is likely to lead to an early death at the hands of the planet's exotic creatures. Slugs, "allodiles", electrically charged blobs, hungry meta-termites and rampaging decapods would be easy to avoid if only you knew where they lived... As there's no RAMSAVE option, saving to disk is essential.

A large part of the extensive environment is immediately accessible so success depends much more on wandering around and discovering what you have to do than performing a series of specified tasks. Topologika describes the difficulty level as standard; I would venture to say that beginners would find some of the problems, which aren't always logical, harder than that to solve. Timing is of the essence, false moves early on can cripple progress later and no clues, however cryptic, should be ignored. You may find yourself succumbing to the on-line help system (which is very careful not to give too much away) more often than usual.

The process is made all the tougher by the absence of an EXAMINE command; most Topologika games assume that you take in everything at first glance. This is more realistic than a laborious search for something you are more than capable of seeing, but it also means that it's impossible to hide clues to the use of a particular object in its description. In some cases, notably a rod which can only be used once, you have to activate the object to find out what it does, then start again to make proper use of it.

£9.95 buys you a fairly complex parser which comprehends most complex commands. It is rather choosy, however, about the precise input needed to complete certain actions. This is one area in which the hint system could he more helpful. The wording of a hint itself doesn't always correspond with the phrase the program will accept I still haven't worked out how to pick up an object with a fishing net. The obvious commands GET X WITH NET and CATCH X WITH NET have no visible effect.

Still, these aren't typical hiccups and the obvious complexity of Countdown To Doom makes up for the occasional limitations of the parser. Certainly, if you enjoy the sort of game which involves hours of careful exploration, Peter Killworth has added enough puzzles, hidden pitfalls and encrypted conundrums to make the long and hazardous journey more than just worthwhile. To begin the countdown contact Topologika at FREEPOST, PO Box 39, Stilton, Peterborough, Cambridgeshire PE7 3BR.