Akari Puzzle Glossary — All Terms
Light Up / Illuminate — To "light up" or "illuminate" a cell means that at least one bulb's line of sight reaches it. When you place a bulb, it illuminates every white cell in its row and column until blocked by a wall.
Each bulb casts light in four cardinal directions. The light passes through white cells but stops at black walls. A white cell is "lit" if any bulb's light reaches it from any direction. The win condition requires all white cells to be simultaneously illuminated.
Every player needs to understand illumination to track progress. Focus on dark cells — they are the ones that still need a bulb to reach them.
After placing a few cats, look for cells that are still dark (darker background). These need light from a bulb.
For each dark cell, count how many valid positions could illuminate it. If only one position exists, a bulb must go there.
The puzzle is solved when every white cell is illuminated and all numbered constraints are satisfied.
Nothing bad — it is perfectly valid for a cell to be illuminated by multiple bulbs. It is just inefficient. The puzzle only requires that every white cell is lit at least once.
When every white cell is illuminated, all numbered cell constraints are satisfied, and no two bulbs can see each other. GridPaw shows a celebration screen when you win.
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