Light Up Puzzle
Light Up
The theatre of illumination
Light every room without letting two bulbs see each other.
How to play
Bulbs light up/down/left/right until blocked. Numbered cells show adjacent bulb counts, and bulbs must not light each other.
Lighting without blind spots
A bulb lights four directions until a wall, but it cannot see another bulb. Look first for positions that illuminate long corridors rather than simply placing more bulbs.
Once a numbered wall has its required bulbs, its other adjacent cells are forbidden. If its remaining cells equal the number of bulbs still needed, every one of those cells is forced.
Origin & history
Light Up (Akari) is a Nikoli logic puzzle where you place bulbs to illuminate every white cell.