StoneForgeLabs

In development

Steam · Q4 2026 · Windows + Linux

Every coin you earn, you can see happen.

Marble Mill is an idle game with no abstract ticking number. A marble rolls, hits a peg, chimes — and a coin pops out. Buy an upgrade and the mill physically rebuilds itself.

Play demo of Marble Mill on SteamWishlist on Steam: Marble Mill
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  • Casual
  • Idler
  • Incremental
  • Cozy
  • Relaxing
  • Physics
  • Short
Marble Mill capsule art: golden marbles on the mill's rings under the game's title

This game ends. On purpose.

~3 hours to the finale — a real ending, with credits. Then an endless sandbox.

~3 hours

To the finale — a real ending, with credits. Short by design.

100% achievements

All reachable in one evening. No grind wall, no season pass.

No dark patterns

No microtransactions. No “wait 4 hours or pay”. No ads. Ever.

ASMR mode

One key hides the whole interface. Just the machine and the chimes.

The mill is an instrument

Every hit is pitch-quantized to a pentatonic scale, so a thousand random collisions come out as a chime melody instead of noise. Each era raises the root a fifth — you can hear your progress with your eyes closed.

At full tilt the mill fires around 1,900 collisions a second. It doesn't get louder — it gets denser.

Copper C a muted wooden tock
Silver G brighter, rounder
Gold D bell-like
Diamond A glass

Good to know

There is no offline income — the mill runs while you're watching it. This is a game you sit with, not a tab you check. Runs on integrated graphics; it's meant for a laptop on a quiet evening.

Play demo of Marble Mill on Steam Wishlist on Steam

Where it is in the lab

  1. Experiment
  2. Testing now
  3. Selected
  4. In development
  5. Released

Becoming a full game. It's heading to Steam.

From the lab