💡 Grid Blackout

Midnight maintenance on the city grid. Your job: darken the whole neighborhood. Click one light and it flips together with its four neighbors — the block only counts as done when everything is black.

Block 1 Moves 0

Grid Engineer Strategy

Light chasing. The classic method: sweep row by row — to darken a light in row N, click the cell directly below it in row N+1, keeping the rows above completely dark.
The bottom row is the crux. Once the top rows are dark, the bottom row's pattern is already decided; figure out which top cells fix it — or just reshuffle, the scramble is random.
Order doesn't matter. The same set of clicks always produces the same result — a wrong move can be corrected, never "ruined".
Crosses cancel. Overlapping cells of two clicks cancel out — clicking the same cell twice fully undoes it (at the cost of two moves).
Don't fear the move counter. Any solvable 5×5 board can be darkened in at most 15 effective clicks — less than half the board. Structured trying beats random clicking.

📖 Read the full Grid Blackout guide →