How to Play Kuromasu
Kuromasu ("black squares") is a Nikoli puzzle about lines of sight: every number is a lookout counting how far it can see before a black square blocks the view.
The rules
- Some squares hold a number. Blacken other squares.
- A number equals the count of squares its square can see in the four directions, itself included, stopping before a black square or the edge.
- Numbered squares are white. No two black squares share a side.
- All white squares connect into one area.
Playing on kawu
- Tap a square once to blacken it, twice for a dot (surely white), three times to clear.
- Numbers turn green when their view is exactly right and red when they already see too few. A warning appears if blacks touch or whites are cut off.
- Undo steps back; Hint fixes a wrong square or adds a correct black.
- Sizes 5×5, 7×7, 8×8; the daily puzzle is a 7×7 shared by everyone.
Next, read the Kuromasu solving tips.
Frequently asked questions
Does a number count its own square?
Yes. A number is the squares visible in the four directions plus itself, so the smallest possible number is 1 (all four neighbours black or off the board).
Can black squares touch diagonally?
Yes. Only sharing a side is forbidden; corners touching is fine.
Last updated 2026-10-20