Luanti, the free and open source survival game engine formerly known as "Minetest"!
I'm pretty late to the party on this one, because I've been hearing about this project for years. But I've finally gotten into trying it out and it has been a ton of fun!
At a basic level you can think of it as a free and open source reimplementation of Minecraft. But there's actually a whole lot more to it than that because Luanti isn't just a single game with a single set of entities and rules, but actually an entire platform for making a wide variety of voxel-based games. It's extremely modular and all written in Lua, so there are a lot of opportunities to customize the experience and every server you join can be wildly different. There's everything from classic Minecraft-esque survival and create experiences, to Factorio-esque automation games, and even weird little experiences and silly PvP servers.
So there's a lot of stuff to explore in the Luanti community, and I've been having a lot of fun with it. I've joined other people's servers, I'm self-hosting another one for my friends, and I've even started hacking in some mods that I think will make the game even more fun for our group.
I can totally recommend it to anyone who has even so much as a passing interest in Minecraft-like games.
Outside of that I've been enjoying other video games lately, including Zelda Ocarina of Time Switch 2, Age of Empires 2 Definitive Edition, and Sonic Robo Blast 2 Kart.