FREE DEMO OUT NOW. Play it alone or with a friend.

A co-op digging game for one or two players. You start in a tiny clearing in the middle of solid rock, with no gravity and no map. Throw a ball and it bounces until the rock stops it. Then throw another.

Two players, one cave. Invite a Steam friend, or hand anyone your cave code. A friend can drop into a cave that's already running, and each of you throws at your own pace.

Nothing slows a throw down here but the rock. Every ball keeps flying until its hits run out.

One splits into three. One drills a dead-straight tunnel. One blows a hole in the wall. One rots the rock from the inside, one zaps everything near it, and one pulls your other balls to where it lands. Then pick how to throw them: a single shot, a fan, a wall of shot, or a sentry that keeps firing on its own.

Everything you mine rattles down a pachinko board, and where it lands decides what it pays. Crates buried in the rock hold the upgrades for the machine, and the further out you find them, the richer they get.

Hundreds of upgrades, on a map covered in fog. Buy one and its neighbours light up.

Four stones are buried out in the dark. Break a pair and a line points the way. Break all four and the one golden piece wakes up. Deep out there, crystal shatters in a ripple from a single hit, and ringing metal shrugs off everything but your special balls.

Also in the game

• Online co-op for two players through Steam
• Mouse and keyboard, or the whole game on a controller
• 13 interface languages
• Colour-blind mode and larger text
• Five save slots, and you can keep digging after you win