Graphics wise this game is pretty good but on the playability stakes it's a dog! It took us ages to work out exactly what we had to do - the instructions are a little unclear to say the least. But we did finally manage to discover that the idea was to pick up pulses of energy in order to destroy all aliens in the space station. Control is a bit haphazard and it's a real pain to re-define the keys after each game. As far as strategic shoot 'em ups go this is certainly not one of Mastertronic's best - you'd be better off buying Thrust!