How to play
Stostone — ストストーン — is a Nikoli puzzle about stones that fall.
- The bold lines divide the grid into rooms. Shade cells to build one stone in every room.
- A stone is a single connected block of shaded cells, and it never leaves its own room.
- A number in a room says how many cells that room’s stone covers. A room with no number holds a stone of any size.
- Stones in different rooms never touch side by side. Corner to corner is fine, and cells of one stone touching each other is the whole point.
- Now let the stones fall straight down, each keeping its shape. They must land filling the bottom half of the grid exactly — no gaps below the halfway line, nothing left above it.
Tap a cell: shade it > mark it empty > clear it. Half the grid ends up shaded, and the counter keeps track.
The rules in full