Having looked at the cassette inly I was looking forward to a few hours' worth of Uridium-style shoot-'em-up fun from Diamond. no such luck though - it just goes to show that you should never judge a game by its screenshots.
The semi-literate waffle that passes for a plot talks about five prison ships which are approaching your home planet, ready to disgorge their captives, who have mutated into monsters over the years due to something called 'Advanced Strogenic Regeneration'. As planetary head honcho you are in command of the five Supertronic Space Craft sent to intercept the prison ships.
So far so good. After struggling with the fiddly control menu I was all ready for a bit of mindless mayhem - at which point the game developed a conscience and decided to take pity on the poor monsters. So instead of merrily blasting the prison ships, your goal becomes simply that of landing on the outer hull of each one and attempting to prevent the prisoners from escaping.
As you approach each ship you'll see a number of holes blasted in its hull. If you're lucky there may be a few prisoners fleeing into space (shoot 'em down while you can) but your main task is just to approach the damaged hull and seal it by firing upon it. This turns out to be on of those things that has to be done with pixel precision (well, almost) and it took me ages to get the hang of it. Not that I felt much better when I did manage it.
You will come under attack of course, but generally your own ship moves so slowly that you won't be able to dodge. Your only other option is to release some 'Inertia Field Modules' to protect you. These might be effective, but they're no substitute for a bit of high-speed ducking and diving.
To slow things down even more the Supertronic craft operate in four different modes, and as you explore the surface of the prison ships it's frequently necessary to switch between modes in order to recharge/defend yourself/take-off/ and land. If you get hit you'll find that your energy levels drop pretty quickly, and the only way around this is to leave the ship in Solar mode to recharge itself. While this is happening you can take control of another ship and go through the whole thrilling rigamarole with that one.
The game is marginally less boring than the two songs that come on the second cassette in the box, but if you don't buy the game then you won't have to listen to those either.
A non-violent shoot-'em-up - what's the point?