Lights Out Puzzle
Switch every light off. Each press flips the cell and its four neighbours. Boards from 3x3 to 6x6, always solvable, with a hint that names the next useful press and your record for every numbered board.
Switch every light off. Each press flips the cell and its four neighbours. Boards from 3x3 to 6x6, always solvable, with a hint that names the next useful press and your record for every numbered board.