You hit them. A number goes up. That's the only thing that still makes sense.
There's a machine, a hammer, and holes that keep producing moles that used to be something else. You hit them. A number goes up. You keep hitting them, because the number going up is the only thing that still makes sense.
Nobody tells you the rules. You learn them by losing — by swinging too slow, by trusting the wrong hole, by letting the wrong thing get away. Every mistake tightens the rope, and the room starts agreeing with it: the light bends, the edges close in, and whatever's underneath the board starts listening.
There's a phone on the wall. It doesn't ring often, but when it does, it already knows what you owe. Pay it, and you keep playing. Don't, and you find out what happens to contestants who stop being useful.