Spillway – Chain Puzzle

SPILLWAY — A SANDPILE PUZZLE GAME

One grain too many, and everything spills.

Spillway is a minimalist brain puzzle about chain reactions. Tap to drop grains of sand, watch overloaded cells topple into their neighbours, and ride the cascade to sculpt the board into the target shape — before you run out of drops. It looks calm. It plays like a chess problem.

Built on the famous Abelian sandpile — the same chip-firing model mathematicians use to study how complexity self-organises — Spillway turns one elegant rule into puzzles that stay surprising from the very first tap.

▸ HOW TO PLAY
• Drop a grain — tap any cell to add a single grain of sand.
• Four topples — when a cell reaches 4 grains it spills, sending one grain up, down, left and right.
• Chain reactions — each spill can tip the next, firing long cascades and big combos.
• Match the target — shape the grid into the target pattern before your drops run out.

Ten seconds to learn. The depth arrives the moment one tap triggers a twelve-step chain you never saw coming.

▸ A NEW PUZZLE EVERY DAY
The Daily Puzzle is one shared challenge for everyone, everywhere. Solve it, beat your best time, and build a streak — miss a day and it resets, so keep coming back. Hunt for sub-10-second solves and climb the global leaderboards.

▸ ENDLESS PRACTICE
Begin with hand-crafted tutorial levels that teach the toppling rule one idea at a time, then unlock an endless stream of fresh, procedurally generated puzzles that ramp up as you sharpen. There is always one more board.

▸ FEATURES
🔥 Daily streaks and milestone achievements — 3, 7, 15 and 30 days
🏆 Global leaderboards and ranks through Google Play Games
⏱ Personal records — best time, best streak, longest combo, total solved
🧩 Endless puzzles, from gentle 3×3 grids to large, dense boards
🎧 Crisp, satisfying topple sounds — mute any time
📴 Plays fully offline — every puzzle is generated on your device
💛 No banner ads and no forced interstitials — the only ads are optional rewarded videos you watch for bonus lives

▸ DESIGNED TO BE HELD
Warm espresso tones, sand-grain texture, and a quiet neon flourish the moment you win. Spillway is made to feel as good as it looks — a tactile little world that suits a five-minute break or a late-night puzzle binge.

Whether you love logic puzzles, brain teasers, strategy games, daily challenges, or just the oddly satisfying physics of a chain reaction, Spillway is a calm, clever puzzle game you will come back to every day.

Drop a grain. Start the cascade.