How to Play Nurikabe

THE PLAYBOOK · TJHAIZHONG

How to play Nurikabe

Try Nurikabe at your own pace and keep its objective in view. Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block. Look at what changes after your first action. Begin with the solo mode shown on the page. Use the example below to understand a decision.

Play ten compact 5×5 puzzles. Some boards begin with fixed shaded sea cells.

Review a difficult moment

When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round. Refer to the controls when needed.

Your goal

Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block. Use the instructions to see which actions move you towards it. Try to explain the aim in your own words.

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. Use the control method described here for this activity. Avoid pressing the same control repeatedly while a move is being processed.

A useful example

An island labelled 1 is already complete, so its edge neighbours must be sea. Use the example as a guide rather than a substitute for reading your board. Verify the rule before continuing.

Watch out for this

Two numbered islands may not merge into one. Compare the situation with the worked example. Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart.

Common questions