Minecraft

Minecraft's design is almost aggressively simple, a grid of cubes you can add to and take from, and the reason it has not been displaced is that nobody has found the bottom of it. Redstone alone has produced working processors. The modding scene has produced entire genres. Servers have produced economies, governments and long-running wars that have nothing to do with anything Mojang built.

Played straight, survival mode is a well-tuned loop: gather, build shelter, get better tools, go somewhere more dangerous. Played with other people it becomes a shared project, and that is where it is at its best. The Java edition is the one to get if you care about mods and community servers; Bedrock is the one to get if your group is spread across consoles and phones.