This is the BBC version of a game that scored a hit in other versions. And it's good stuff, a combination of Repton-like maze and fast arcade action.
You control Blob, the Biologically Operated Being, whatever that means. His daunting task is to rebuild an unstable planet from within, to stop it exploding and destroying the universe.
This is the thin excuse for a lively adventure in which you explore a vast maze (500 screens, says the blurb), meeting a host of objects and aliens. You can move left and right, fire at nasties, pick things up, and lay bridging platforms. The only use I could find for this latter feature was to propel Blob upwards. You can define your own keys, and there is a joystick option.
Features include anti-gravity lifts, pyramids, secret passages, teleports, lunar undergrowth and a lot of other things I either didn't encounter, or failed to recognise. This is one of those games which you have to play for a long time to find out what's going on, what you're supposed to be doing, and what all the weird and wonderful objects are.
The graphics are pretty good, nifty with smooth animation. The maze design reminds me of Repton, with gravity. The sound is lively too.
Now if you'll excuse me, I have a planet to rebuild...