Luanti (Formerly Minetest)

I've converted a few old Minecraft worlds. It required some Python on the command line, and some retries with edited configs, since I had Minecraft mods and wanted some unexpected objects to come over.

This seems to be a nice recipe: https://vlwiki.phinetwork.ch/index.php/Importing_from_Minecraft

To answer your other question - I recommend going into crazy modding in Luanti later, it's great.

But for the closest experience to vanilla Minecraft, there's VoxeLibre - which is also the import target for the above script.

VoxeLibre is a full Minecraft implementation until about a year or two ago, when it diverged and focused on its own unique new game features. So the early game is nearly identical, but my understanding is that the late game is expanded and different.

(I didn't play through the late game in VoxeLibre, because the siren song of Minetest plus crazy mods pulled me away and I've been focused on playing with model trains with the Advanced Trains mod. I thought I needed a bare install MineGame to be sure Advanced Trains ran stable. Now, having run a server for awhile, I suspect Advanced Trains might have have just worked fine on VoxeLibre.)

Honestly best thing about Luanti is being able to fuck around and code.

For kids you want UltimMC Minecraft launcher and a heavily-customized modpack. Most modpacks are just giving these kids absolute fucking slop without any attempt to balance or integrate the mods & declutter REI/JEI.

I have been addicted to Modrinth on and off for years so I'd be happy to provide recs but I understand if this is some kind of ideological pure libre thing that will be of no interest.

Why am I telling you to not force your kid to play Luanti right off the bat? Well, becoming exasperated with modding is how I sought it out. I got into modding because I played some real good mods and integrated them until the integrations became their own mods.

Get that little guy Create mod! Luanti has its own unique qualities (but nothing like that) it's fun for building like, a fusion of Minecraft and Portal 2.

Okay, I copypasted this question to the Luanti forums. In case someone else wants to follow that discussion, here's where: https://forum.luanti.org/viewtopic.php?t=32372

My advise: don't

Forcing a kid to do something makes them hate it

I had no idea Minetest rebranded but the last time I played it had several mods that made it almost identical to Minecraft, even having the same textures.

Don't know about conversion, you should try asking on reddit or the luanti forums :)

The closest Minecraft like game is mineclonia, creative mode is kind of built-in but I don't think it disables damage, (I don't know how mineclonia handles it).