THE PLAYBOOK · CDBRM
How to play Nurikabe
Nurikabe on CDBRM is organised around a clear objective: Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block. Begin with careful restarts and use the playbook beside the game.
Ten checked compact 5×5 boards with fixed sea starters in some puzzles.
Careful restarts
Start a fresh round when you want another attempt. Restarting may discard current progress; read the controls rather than assuming an account backup exists.
Your goal
Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block.
Step by step
- Shade sea squares and leave islands white.
- Every island contains exactly one clue.
- Different islands cannot meet along an edge.
- 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
Which play mode is provided?
Solo
What is the main objective in this edition?
Create one connected sea around numbered islands of exactly the stated size, without a 2×2 sea block.
What mistake should I watch for?
Two numbered islands may not merge into one.
