How to Play Nurikabe

THE PLAYBOOK · PT-BUS

How to play Nurikabe

For Nurikabe, PT-BUS puts the actual rules alongside the playable board or activity. Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block. The suggested practice focus is understand the boundary.

Ten checked compact 5×5 boards with fixed sea starters in some puzzles.

Understand the boundary

Check the edition notes and play mode. A local game, a computer opponent and remote multiplayer are different features.

Your goal

Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block.

Step by step

1. Shade sea squares and leave islands white.
2. Every island contains exactly one clue.
3. Different islands cannot meet along an edge.
4. Check puzzle verifies sizes, connectivity and forbidden sea blocks.

Controls

Click or tap squares or graph edges. Number boards include a digit pad. Undo reverses the previous change; Check puzzle validates the solution.

A useful example

An island labelled 1 is already complete, so its edge neighbours must be sea.

Watch out for this

Two numbered islands may not merge into one.

Common questions