I’d second Luanti, but just clarify that these days it’s more of a game platform than a single game. It has a built in content management system to download games, mods and texture packs.
The games available to install via Luanti range from Mincraft clones like Mineclonia, to semi-clones like Voxellibre, to original blocky survival games like Exile, all the way to arcade style games Extra Ordinance and platformers like Glitch, where you’d swear they were built on a totally different engine.
Mods for Luanti games are also pretty great, everything from fully fledged train systems to airships and everything between.
https://content.luanti.org/packages/Sumianvoice/extra_ordinance/
Sorry was too lazy to link everthing. Extra Ordinance was more an example of the fact that Luanti can do all kinds of stuff and it’s a single game.
These might be more to your taste:
https://content.luanti.org/packages/Wuzzy/mineclone2/
https://content.luanti.org/packages/ryvnf/mineclonia/
https://content.luanti.org/packages/Mantar/exile/