PREPARE to eat hot gamma rays, Alpha Centaurian! When you read a sentence like that you know you're either about to read an excerpt from Niven and Pournelle's Football, or it's the start of another shoot-'em-up review.

In this case it's a review, but before you start complaining, it isn't an ordinary run of the mill, seen it before, read it before review. No siree, because this is a review of the best sideways scrolling shoot-'em-up ever released for any home computer.

Now you all know that those spoilsports at Activision made US Gold keep Katakis off the market until after Christmas because it was so similar to R-Type. Well a few changes were ordered to while away the programmers' time, including the name, and now it's back, better and badder than before. It's a total blasting experience.

It all begins quietly enough with a parallax scrolling starfield filling virtually all of the screen save a small control panel at the bottom.

In troops an attack wave of laser fodder. Waste 'em. An icon pops up. Run it over and a nose appears from the stores, floating behind you. Go back and collect it. The nose is the essential accessory for trendy blasters, the difference between life and death.

Suddenly metallic-blue scenery scrolls in, missiles come hurtling towards you, stompers stomp across the bottom and floating aliens fire repeatedly. Before you can draw breath the next icon makes an appearance. The phoney war is over, the serious action starts here.

All this lot was actually level two of Katakis, but it has been modified and made easier to form the introduction to Denaris.

On you fly, encountering spiralling attack waves, laser gates dropping from the ceiling, large blocks which pile up blocking the way, hopping aliens, running aliens, aliens on jetbikes, aliens selling ice creams - only kidding - and not forgetting those lovely icons.

After dispensing with one huge mother of an alien at the end of the level, it's shock horror time on level two as throbbing spheres and wicked looking boomerang-style attacks are just a foretaste of what is to come. Scenery with nasty barbs and tricky passages is the order of the day. More jetbikers on a road to nowhere are just waiting to die for the cause of entertainment. Then again, I do hear the pay is good.

Tumbling panels - which were first seen in Xevious - and a swirling field of spacemines are two more of the hazards to be overcome before you get to really difficult stuff on level three.

This is a grey metallic hell with little room to manoeuvre and less time to react. Indeed the challenge at the end, which is a total R-Type steal involving a mechanical snake-like device, is impossible unless you have protective pods to keep out the point blank firing.

Around this time you might have collected what I take to be the final weapon to add to your arsenal - homing missiles. My, are they fun!

If you are looking for a game that needs fast reactions, that delivers a satisfying killing experience, that is the ultimate in sideways scrolling destruction, then look no further. Get a copy of Denaris, get that nose, and give those Alpha Centaurians some hot gamma rays.

Those galactic fiends are at it again. You give 'em just enough time to get over your last attack and what do they do? Repair their lasers and start shooting photons at you again. Denaris, previously named Katakis, is US Gold's answer to the hugely popular R-Type.

The Amiga version of Denaris is virtually a completely different game, bar the fact that they share the same plot and scroll the same way. It is nevertheless a very slick, albeit unoriginal, arcade game, which, if anything, owes even more to the original R-Type than its 64 counterpart.

The gameplay is the same, with you controlling the ship shooting the nasties and every so often receiving an icon to increase your shield and firepower with the same kind of weapons (bouncing lasers, homing missiles and a beam laser). Otherwise, the levels and most of the aliens are completely different to look at.

The only moan I have is the loading time between games though when placed up against Op Wolf on the Amiga it seems mercifully short (if you can call a minute short for restarting a game).

It is impossible to compare Amiga Denaris with the same game on the 64. What I can say is that it is another fantastic arcade shoot em up with all the vital additions essential for a great blast - hot graphics, a hot soundtrack coupled with neat sound effects. Denaris is very, very addictive. The number of levels and its toughness make it excellent value for money. Somehow, for me it does not quite match the playability of the 64 version. Still, that is no reason why 16 bit owners should turn down what is probably one of the finest Amiga shoot em ups to date.