If nobody does it before me, I will attempt to make some rock-ground tomorrow after I got some sleep, which I am in a dire need of right now.


I envision the tileset to be cave-like, however, not exactly a cave.. besides, caves are overused in any genre of games.
Imagine a mountain or canyon with extremely complex cavern systems inside. You can see mountains in the background, through cracks, big holes and openings in the mountain walls, maybe a river flowing there, a canyon would be a nice idea, I think.
And inside these caverns, some native society built their homes.
I love the idea. I should make a sketch of what I have in mind to be able to illustrate it better, I think you'd like it.