Why does clicking one cell flip others?

That's the core mechanic — each click toggles the clicked cell plus its up/down/left/right neighbours.

Are all puzzles solvable?

Yes — puzzles are generated by starting from a solved state and applying random valid moves, guaranteeing solvability.

Lights Out Puzzle Game

Toggle all lights off! Clicking a cell flips it and its neighbours. Classic puzzle.

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How to play

Click any lit (amber) or dark cell to toggle it and its 4 neighbours.
Goal: turn ALL cells dark (off) at the same time.
Think ahead — each click affects up to 5 cells at once.
Click 'New Puzzle' for a freshly shuffled, always-solvable board.

Toggle all lights OFF. Clicking a cell flips it and its 4 adjacent neighbours. Every puzzle is solvable!

Frequently asked questions

Why does clicking one cell flip others?: That's the core mechanic — each click toggles the clicked cell plus its up/down/left/right neighbours.
Are all puzzles solvable?: Yes — puzzles are generated by starting from a solved state and applying random valid moves, guaranteeing solvability.