About Glow Grid
We built Glow Grid because the toggle-puzzle idea is one of the purest things in the genre and almost nobody serves a clean version of it in a browser. Twenty-five lamps, some lit, some dark. Tapping one flips it and whatever sits directly above, below, left and right of it. That is the entire rule set, and it is enough to keep a board interesting for ten minutes.
The trap is that progress feels like it goes backwards. You light a corner, and the tap that fixes the next square puts the corner out again. Once you stop treating cells as individual switches and start thinking in rows, the board opens up.
How to play
Turn every lamp on. The daily board is generated by scrambling backwards from a fully lit grid, so a solution always exists — usually within four to nine presses, though finding those presses is the puzzle.
Controls
- Click or tap any cell to flip it and its orthogonal neighbours.
- Clear returns the board to its opening state without a new scramble.
- New practice deals a fresh board when you want another go.
Tips
- Presses commute and each one undoes itself, so order never matters and pressing the same cell twice wastes two moves.
- Work top-down. Fix row one, then for every dark cell in a row, press the cell directly beneath it — that pushes all the darkness to the bottom row.
- Whatever pattern you end up with along the bottom tells you which row-one presses you should have made. Restart and try that opening.
- Corners are the most constrained squares on the board; they are affected by only three presses, so solve around them early.
