Moss grows only while you are not tapping. Patience is a resource.
Crumble everything back to gravel. Keep sediment forever.
Every tap knocks loose a bit of grit. Grit is the whole economy. Yes, that is the entire skill ceiling.
Rain, frost, rivers, glaciers, tectonics. Each one grinds grit off you while you do nothing at all.
Moss only grows while you are not tapping. Put the phone down for a minute and come back richer. Moss buys permanent multipliers.
Cracks open up on your surface at random. Tap one before it seals for a burst of grit or a frenzy.
Enough lifetime grit and you graduate: Pebble → Stone → Boulder → Monolith → Meteorite → Mountain → Planetoid → Continent. Each era multiplies everything.
Prestige. Crumble back to a pebble, keep sediment, and every future run is permanently faster.
You keep eroding while the tab is closed — up to 8 hours of grit and 12 hours of moss. Rocks are patient.
Rock Simulator — part of the MiniGames arcade.
Vanilla JS. No engine, no ads, no trackers, no network calls unless you opt into the global leaderboard. Works fully offline.
Sound is synthesised live with WebAudio. Every rock is procedurally generated from your save seed, so yours is genuinely yours.