At first glance, Jawz looks like a variation on Invaders, but with the action transferred from the depths of space to the depths of the ocean.

You control a gun which rests on the sea bed. It can be moved left and right and fired at sharks swimming in mid-ocean.

Close to the surface are jelly fish which drop poison pellets. The sharks appear resistant to the poison, and swim on if hit, but if your gun is struck, you lose it. You get the usual total of three guns before the game ends.

The sharks look more like tiddlers as they swim randomly to-and-fro, doing harm to no one. It seems a shame to blast them out of the water. But this you must do if you want to score any points.

And that's the hard part. For bullets don't fly straight up the screen: instead a 3-D effect is achieved. Two bullets fly out from either side of the gun, and it is only when they converge on a shark that a kill is made. The sharks' movements are fast enough to make that rather difficult.

The faster you kill, the higher your score rate. There is also a time limit (so watch your oxygen level), and three levels of difficulty.

Instructions appear on the screen in between games. They are very limited, and a couple of tries are needed to get used to Jawz.

There are five different keys to press. These are bunched together at the base of the keyboard - a little tricky for adult-sized fingers.

Nevertheless, a must for Invaders connoisseurs who want to try something a little different.

D.N.