OK, we all know how this one goes. A spaceman has to collect eight items from each screen and then reach the exit door. Having also blatantly ripped a whole lot of its patrolling bad guys from Jet Set Willy, Planet Nubium certainly isn't going to win any awards for originality.
What we've got here is typically platform game fare - not particularly bad, and with some surprisingly toe-tapping chiptunes accompanying the action, but far too forgettable to make any impact. The more usual jump control has been replaced with the ability to thrust here, but it remains a tired concept.
Basically, all you have to do is thrust around a hi-resolution screen, collect the eight items, and then enter your spaceship to proceed to the next screen. The first eight screens are almost insultingly easy and I cleared them all without losing a single life or breaking a sweat. After this, they do become a bit harder, with items placed in more difficult-to-reach places. However, I found it all very boring to play. It would've passed for great home entertainment in 1983 for sure, but even us hardened homebrew enthusiasts are going to find it hard to get excited by yet another bunch of serially accessed screens in the Manic Miner/Bug Eyes format in 2021. Let alone when the screens themselves are much less imaginative in comparison.
A sort of patchwork quilt of Microcosm, Manic Miner and Bug Eyes. If you really like those games, you'll probably wrest a few moments of joy from it. But if you're pretty indifferent to them, then there's nothing here to change your opinion.