Puzzlepedia™ Grid Puzzles
Akari
Place lightbulbs into a grid according to certain rules.
Akari (also called Light Up) is a logic puzzle played on a grid of white and black cells. You must place light bulbs in the white cells until the entire grid is lit up. A bulb sends rays of light horizontally and vertically, illuminating its entire row and column unless its light is blocked by a black cell.
- No two bulbs may shine on each other.
- A black cell may have a number on it from 0 to 4, indicating how many bulbs must be placed adjacent to its four sides.
- An unnumbered black cell may have any number of light bulbs adjacent to it, or none.
- Bulbs placed diagonally adjacent to a numbered cell do not contribute to the bulb count.
Sample Puzzle
Solution
Here is an unsolved Akari puzzle for you to try.
Akari Solving Techniques
Here are a few tips and techniques for working on an Akari puzzle.
- When you see a black square with 0 in it, you can draw a little x in the four adjacent white squares because you know a lightbulb doesn't appear there.
- When you see a black square with a 4, you can draw a light bulb in all four adjacent white squares.
- When you place a lightbulb you can draw a line (or highlight) all the squares that are illuminated by that lightbulb. None of these squares can now contain another lightbulb.
- As you progress, keep looking for black squares that have a 1, 2 or 3 in them that also have only 1, 2 or 3 unmarked white squares adjacent to them because these are forced to be lightbulbs.
- Also keep an eye out for unhighlighted squares that can only be illuminated by one remaining spot because the lightbulb must go there.
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