You're an Osmo, a strange creature indeed. You explore the galaxy in your spaceship, and the planets you encounter are almost as bizarre as the Osmos themselves. There are seven worlds presented for your consideration, each more goofy and peculiar than the last. Cosmic Osmo is a game about exploration and discovery, not winning or challenges.
Genuinely one of the most imaginative spaces to mess around in. Like an old website for kids way back when. You can't make it fill the whole screen though, which kinda sucks, and if you click outside of the playable interface, the whole thing breaks...
EDIT: I managed to do some hacky thing, whereby I used ProtonTricks to make the game windowed, then...