It’s the only C64-exclusive game I can ever remember being any good. Admittedly, I only ever had it as a demo from some Commodore magazine cover tape, but still.
And it is pretty good, yes. I’m not a fan of the up-to-jump mechanism so often favoured in computer (as opposed to console) games, especially when it leaves a fire button free and unused as here (well, except when you want to jump down a level, but that just makes the “up” seem even more strange). Pressing up on a d-pad to jump never seems right in a platformer.
Anyway, after about half an hour’s play I realised I had no idea how to actually progress in the game. Turns out you have to collect magic bags (les sacs magiques, n’est pas?), then drop down a hole, then collect stars. So I went back and started again, managing to complete the first level, Jellyland! Hurrah!