There are clowns down there, in the hole.
Dig down deep into the hole. Use what you find to maximise the yield. Hire workers and fighters from the surface to build out your subterranean expedition.
Click on Ore nodes to mine them. Build hiring signs and call down workers to help you mine.
Clowns can be dangerous, but they yield the Blue ore. You must get the Blue at all costs, no matter what comes out of the hole.
Click on the clowns to fight them. Build hiring signs to call down fighters to help you keep the clowns at bay.
Harvest the coveted ore. Take them with you to the surface to bargain for new tools and supplies.
Use your hard-earned ore to progress along an incremental upgrade track, unlocking new buildings and workers. Build up a camp of helpful structures to make your expeditions go smoothly. Well, as smoothly as it can go down there in the Clown Hole.