Nurikabe
Paint cells black or white so every clue is a tidy island.
- Tap a cell to paint it black (wall). Tap again to paint it white (island). Tap once more to clear.
- Every numbered clue is part of a white "island" of exactly that many cells, connected by edges.
- Two islands can't share an edge (corner-touching is fine).
- All black cells must connect into one big group.
- Black cells can never form a 2×2 square.
A tiny board you can experiment on.
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