You can’t really torrent it, the game version gets downloaded when you start it, so you’d either have to torrent every version you want to download or download everything at once, which would take way too much space. The thing is, you don’t even need to. You can make an account without buying the game and you can still play it. There’s dedicated launchers for playing the game with an account that doesn’t own it.
Also, Veloren is not similar to Minecraft at all, even if it’s still a very good game. There’s Minetest tho, which is also open source and it has a gamemode as a mod, which tries to be a copy of Minecraft.