01 · Reflection
Tap a mirror to switch between / and \. A horizontal beam becomes vertical; a vertical beam becomes horizontal. Follow the beam from the orange arrow and solve one turn at a time.
Start with First reflection →02 · Placement
You choose where the pieces go. Select Mirror in the tray, then tap an empty socket. Tap a placed mirror to rotate it. Select Erase, then tap a piece to return it to the tray. Empty sockets are not necessarily part of the solution.
Try Choose your place →03 · Branches
A striped splitter sends one beam straight through and reflects another. Both branches matter. Start at the targets and work backward to the place where the paths can share a source.
Try One becomes two →04 · Synthesis
Choose the positions of mirrors and splitters together. Red sensors must stay dark. A route that reaches every target still fails if an unwanted branch crosses a sensor.
Try Build a branch →A little help
Undo reverses your last edit. A hint removes an unnecessary piece or sets one piece on a known solution. Hints are recorded with your result; you can replay a chapter puzzle to improve it. Daily puzzles keep your first result.
A reason to return
The daily puzzle changes at midnight UTC. Everyone gets the same board for that date. Share your result to invite someone to the same puzzle. Daily completions build your local streak.
Your progress stays in this browser, without an account. It does not sync between devices. Once loaded, the game can work offline in browsers that support service workers; the first visit needs a connection.
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