Hard Nurikabe
Hard Nurikabe puzzles are 8×8 and need a short look ahead: the other choice for a cell breaks a rule straight away, such as walling an island in too small or cutting the sea apart.
Hard puzzles need at least one of these techniques, and may use any easier one:
- Look one step ahead
- The other choice here breaks a rule straight away: a pool, an island too big or too small, or a cut sea.
How to play
Nurikabe is a logic puzzle about islands in a sea. Each number is part of an island with exactly that many cells. Shade every other cell as sea so that the sea is one connected area, islands never touch side by side, and no 2×2 block is all sea.
Every Nurikabe here has exactly one solution and can be solved by logic alone. The grid grows from 6×6 at Easy to 8×8, and the level is set by the hardest technique the puzzle needs.
- Each island holds exactly one number, and its cell count equals that number.
- Islands never touch each other side by side.
- All sea cells form one connected area.
- No 2×2 block is entirely sea.
Playing on this site
- Tap a cell to shade it as sea, tap again for a dot that marks it as island, and once more to clear it.
- Drag across cells to paint the same mark along the way; the whole drag is one undo step.
- With a keyboard, use the arrow keys to move and Space to cycle the mark.
- Dots are only a helper: the puzzle is solved as soon as the sea is right.
- Hint points out wrong cells first, then names the next technique and highlights where it applies.
- Your puzzle is saved in this browser, so you can come back to it later.