🌊 Nurikabe
🧩 Puzzle · 13 playsNurikabe
Flood the board — but the sea has rules and the islands have numbers.
About Nurikabe
The Japanese wall-building puzzle named after a yōkai that blocks travellers in the night. Shade the sea around the numbered islands: each number sits on an island of exactly that many white cells, islands never touch each other, the sea must flow as one single connected body, and — the rule that breaks beginners — the sea may never pool into a 2×2 block. Four constraints, one solution, and a very smug feeling when the last wall drops into place.
How to Play
Tap a cell to shade it as sea; tap again to clear. Each number = an island of exactly that many unshaded cells, one number per island. Islands don’t touch. The sea stays one connected region — and never fills a 2×2 square.
💡 Tips & Strategy
Mark the certain sea first: cells between two numbered islands diagonally adjacent, and any cell two steps between numbers, must be black. Every 1 is finished at birth — ring it with sea immediately.
Use the 2×2 rule as an engine, not a check: three shaded cells in a square force the fourth cell white, and that white cell must belong to some island. Chasing whose it is usually cracks the region.
Count the totals — island sizes plus sea must fill the board, and the sea has to stay one body. A sea corridor one cell wide that is the only link between two halves is forced black all the way. Escort your islands to exact size, then wall them shut.