A cross between simulation and RTS game. You're supposed to build up a colony and manage your society. The details are not too abstract, as all units you see will have individual names and the details of your infrastructure are pipes, conveyor belts, workshops, electrical lines, generators, and so on.

You could say it's a "dwarffortress" except the details are totally different. For example, chopping down trees will not kill dwarves, but it does in my game. Production and logistics in my game is a lot smarter to prevent players from worrying about managing food production so that they can worry about more interesting things.

It's a very ambitious project for sure, and I am not expecting to complete the game until many decade latter. I am in this project at about 4 Kloc of code, yet a completed RTS game is about 40 Kloc. Mine will be bigger than this.

The main challenge in doing this project is whether or not I have the ability to slog it out for several decades and the ability to resist temptation to rewrite the whole codebase at once.