Lights Out has one rule and it's a menace: pressing a light flips it and its four neighbors. Your job is to turn the whole board dark, and every press that fixes one light disturbs the ones around it.
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The board knows the best answer
Every puzzle shows a PAR: the true minimum number of presses. Finish and you're rated OPTIMAL, GREAT, or GOOD against it, and every board is guaranteed solvable, so there's no unwinnable grid waiting to waste your time.
When you're stuck
Press 2nd and the game highlights one press from an optimal solution. It's a nudge, not a spoiler: one press of progress, and the rest of the puzzle is still yours.
Sizes
EASY is a 3×3 board (learnable by feel), NORMAL is 4×4, and HARD is 5×5, where intuition dies and technique takes over. Arrows move, ENTER presses, and your fewest-presses record is saved per size.