Usually I don't have much time for waves of alien shoot-'em-ups, but this one has some very clever features and a nice sense of humour. You have to punch your way through nine screens of nasties (whirling dervishes, interstellar pogos - and find out the rest for yourself) to reach the would-be galaxy conqueror The Master.
Destroy him and he comes back faster and furiouser. Mechanically it's quite tricky because firing is delayed and non-continuous. So you have to lead your target, figuring out where it might be in a split second's time.
Some are fairly predictable, others a good deal less so, but either way your job is complicated by having the screen full of other lethal, but unhittable, horrors that simply absorb your fire, and your standard rain of missiles. Between screens you get sardonic messages from The Master and when you run out of lives you get a mocking that varies in rudeness depending on the level you blow out on.
Rather usefully, you can call up any level but the last for a dry run. Fun, but I doubt if it's anything like tough enough for hardcore Starfighter types.