Shade cells to satisfy the number clues. Each number shows how many black cells are visible in all four directions.
Each number tells you how many black cells are visible from that cell, looking up, down, left, and right to the grid edge.
Click or tap a cell to shade it black. The number counts all black cells it can "see" in straight lines.
All white (unshaded) cells must form one connected group. You cannot isolate white cells with black cells.
You cannot have a 2x2 square that is entirely black. At least one cell in every 2x2 area must be white.
Use hints (3 per puzzle) when stuck. Right-click or long-press to mark cells as definitely white (dot). Use undo/redo freely.