How to Play Akagram: Rules, Controls and Examples
Learn how to play Akagram with clear rules, bulb and empty marks, and a worked 6×6 opening. Understand Check, Hint and what counts as a finished puzzle.
Akagram Rules: Light, Walls and Bulb Counts
Place bulbs on open cells so every open cell receives light. A bulb lights its own cell and shines horizontally and vertically until a wall or the edge of the board. Light does not turn corners. Two bulbs must never see each other along an unbroken row or column.
A numbered wall tells you exactly how many bulbs touch its four sides; diagonals do not count. An unnumbered wall has no adjacent-bulb requirement. Numbers outside the grid count bulbs in the whole row or column, including cells on both sides of walls. They count bulbs, not illuminated cells.
Akagram Controls: Bulbs and Empty Marks
Start a board, then click or tap an open cell to cycle through undecided → bulb → × → undecided. The × means you have decided that this cell has no bulb; it can still receive light. Walls cannot be changed. Use the arrow keys to move between open cells and Enter or Space to cycle the focused cell.
The board finishes automatically when every open cell is lit, every clue is satisfied and no bulbs shine on each other. You do not need to mark the remaining cells with ×. A move being accepted does not prove it is correct: conflicting marks can stay on the board so you can inspect and undo them.
Your first deductions on a real 6×6 board
This is 6×6 puzzle #1. Count rows from the top and columns from the left. The numbers above and beside the grid are bulb totals. These three steps show a starting position, not the complete solution.
| Row / column bulb totals | 2 | 0 | 1 | 1 | 1 | 1 |
|---|---|---|---|---|---|---|
| 1 | · | · | · | · | · | · |
| 1 | · | ■ | ■ | ■ | 0 | · |
| 0 | ■ | ■ | · | · | ■ | · |
| 2 | · | 1 | · | · | · | · |
| 1 | · | · | · | · | · | · |
| 1 | · | 0 | · | ■ | · | · |
- Observe: row 3 has a total of 0. Rule: its bulb count must be exactly zero. Conclusion: mark every open cell in row 3 with ×.
- Observe: the wall at row 2, column 5 is numbered 0. Rule: none of its side-neighbors can hold a bulb. Conclusion: mark row 1, column 5 and row 2, column 6 with ×; its other two neighbors are walls.
- Observe: row 2 needs one bulb and has only two open cells. One is now marked ×. Rule: the row must still reach its total. Conclusion: place a bulb at row 2, column 1.
| Row / column bulb totals | 2 | 0 | 1 | 1 | 1 | 1 |
|---|---|---|---|---|---|---|
| 1 | · | · | · | · | × | · |
| 1 | ● | ■ | ■ | ■ | 0 | × |
| 0 | ■ | ■ | × | × | ■ | × |
| 2 | · | 1 | · | · | · | · |
| 1 | · | · | · | · | · | · |
| 1 | · | 0 | · | ■ | · | · |
Undo, Reset, Check and Hint
Undo takes back your last board change. Reset clears your marks on the current puzzle. Check asks whether your current bulbs and empty marks can still lead to a completed board. An OK result is not a win and does not mean every undecided cell is settled. If Check cannot finish its search, the result is inconclusive, not proof of a mistake.
Hint places one forced bulb or one forced empty mark and identifies its row and column. It does not explain the deduction. After a successful hint, wait five seconds before the next one. If no forced move is found, Hint leaves the board unchanged. There is no pasted-grid or image-upload solver on this site.
Why a Fully Lit Board May Not Be Finished
Light shows that a cell is illuminated; × is an optional note that a cell has no bulb. You can leave non-bulb cells unmarked and still win. Crossed beams on an empty cell are allowed, but two bulbs must not shine directly at each other.
If the board still does not finish, look for an unlit cell, two bulbs shining on each other, an incorrect row or column total, or a numbered wall with the wrong adjacent bulb count. Diagonals do not count toward walls, and empty marks do not block light.
For a repeatable way to choose your next move, read Akagram strategy.