Black Colo
Shade cells so each number counts its neighbouring black cells.
Controls
Shade some cells. Shaded cells may not share an edge, and the unshaded cells must stay orthogonally connected. A number cannot be shaded; it counts how many orthogonally adjacent cells are shaded. Tap a cell to cycle empty → shaded → white, then use Clear and the answer button.
Brain training · PuzGo