🔆 Lumen

How to play Lumen

1. Pick a grid size, then press Start.
2. Every cell glows at one of three levels: dark, dim or full.
3. Tapping a cell lifts it and its four neighbours by one level, wrapping full brightness back to dark.
4. Raise every cell on the board to full brightness to win.

Controls

Tips & strategy

• Work top-down: fix the top row, then use the row beneath each cell to correct it without touching finished rows.
• Three taps on the same cell changes nothing, so you never need more than two on any one square.
• Count levels modulo three — a cell that reads 'dim' needs two more lifts, not one.
• Your best is the fewest taps to solve, tracked separately for each grid size.

Frequently asked questions

How is Lumen different from Lights Out?

Lights Out is two-state — on or off. Lumen has three levels and taps cycle through them, so you have to think in threes instead of simple flips.

Is every board solvable?

Yes. Each board is made by scrambling a solved grid with random taps, so a tap sequence back to full brightness always exists.

How is my score tracked?

Your record is the fewest taps to light the grid, saved per size in your browser.