A unique type of game that makes Minetest not be a copy of you-know-what-sandbox-game
In this game you don't build on craft tables etc. but you assemble everything in front of you on the ground. This feels very natural. I love the minimum set of nodes where game complexity emerges purely from combination of the few things you have. This is very different from, e.g., MT Game, where you have so many different ores and jewelery, most of which are more or less useless, or just for decoration. In Nodecore, the blocks themselves have only basic functionality, there are no sophisticated furnaces, doors, electronics, but only flammable materials, hinged blocks (nice idea) and other stuff I still need to discover.
The list of challenges usually gives you enough guidance to reduce the number of things you need to try. At least for me, that is. I got to metallurgy, hinged panels etc. without external help. Let's see if I can invent automats. The game has many ways to build machines from a handful of basic elements. Ways I still have to discover :)
But beware: the game is a time sink. I only got this far because I have played it for ~30h and more. In classic MT, this is enough time to gather tons of many different materials, build super-armor, weapons and a cool castle. Something that is not the goal in Nodecore. Already building a simple house from beautiful materials is tedious. You will know what I mean when you see that you need to mix materials with ash, put water on them, let them dry, shape them to your favourite look and finally cook them, and this for every single block of your house's walls.
On the other hand, in multiplayer, having a nice little house is something to be proud of in Nodecore :)
Excuse me, need to go now and find some of that darn "Lux" ore...