Blastboom Strice

Not european, but the nonprofit Metabrainz foundation has related open source projects, like musicbrainz, listenbrainz, critiquebrainz etc. where almost every data is liscensed with CC0:

https://metabrainz.org/projects

Hmm, how about mindustry (its open source and free outside of steam)? It’s like factorio with tower defense. Note: after playing for few hours you might get access to many more stuff in game which might feel overwhelming

This probably wouldnt make sense in a decentralized platform- oh

(Dunno if it’s apparent, but this is a criticism to the bluesky platform being heavily centralized)