Luanti is a free open-source voxel game engine with easy modding and game creation. This is a custom build of Luanti 5.16.1 with VoxeLibre 0.92 (Preview), but more games will be added soon!

kaesual.com gives you a virtual IPv6 address to play peer to peer with other players - no game server required. This is not your real IP address, and it will only work in this Luanti version.

If you create a world, just enable "Host server" and share your virtual IPv6 address with your friends. They can then join by entering your virtual IPv6 address in the "Join game" menu. You can also join other players' worlds.

Install game packs from the Content tab, tweak settings under Settings, and manage your saved worlds in Worlds. Worlds persist across browser restarts — but downloading a backup after a long session is still a good idea.

My Luanti version is open source - you can find the source code on GitHub: https://github.com/kaesual/luanti/tree/web
Have fun!

Tip: There is a VoxeLibre server running on kaesual.com, you can find it in the "Join game" menu.