How it works
The orange start fires once. Arrows travel up to three squares, light every ring they cross, and stop at the first relay. Each relay fires once, in its arrow directions. Arrows can cross empty spaces. Select a placed relay to rotate or move it. Every puzzle has at least one perfect solution.
On a keyboard, Tab to a socket and press Enter to place. Press R to rotate the selected relay. Daily runs are timed from the moment you reveal the board; Free Play has no timer.
About this game & playtest data
One Spark is free to play. Free Play stays on this device. A daily result is only added to the public leaderboards when you create an account and verify your email; your email remains private and your chosen display name is public.
The daily puzzle changes at midnight UTC. The clock includes retries and time away, so the leaderboard rewards a clean, honest completion. Achievements never reset. Clearing browser data removes an unclaimed guest run.