A little illumination
Light Up
Place bulbs using visibility and numbered clues.
THE OBJECTIVE
Think it through
Light every white square. Bulbs shine along rows and columns until a wall, and must not shine on one another. Numbers specify adjacent bulbs.
YOUR CONTROLS
Make your move
Click a square to place a bulb; right-click to mark a square that cannot contain one.
On a phone, use Touch: mark / reverse for a right-click action. Number puzzles include an on-screen number pad.
Choose an easier or harder grid in Type. Use Undo freely. Reveal solution shows the answer; it is a learning aid, not a hint. Use Finish & review to record practice time and actions. Complete 60 seconds of unrevealed practice with at least 3 board actions for the daily streak. Your last puzzle saves in this browser when device storage is available. Use Game → Download save file for a portable backup.
Puzzle engine by Simon Tatham and contributors · MIT licence · Full rules ↗