Catch the
signal.

How to play Pulse Lock

Stop the orange needle inside the blue arc. Each new lock gets faster and tighter; late locks can shift the target while the needle moves.

1. Choose a daily course or a fresh practice course. Start the signal and watch the orange needle.
2. Tap Lock now when the needle enters the blue arc. The middle third counts as a perfect lock.
3. Complete twenty locks with three lives. Misses break your chain, and late locks may feint to a new target. Select Next lock when you are ready.

Controls and accessibility

Tap or click Lock now, or press Space when a form control is not focused. Enter or Space activates a focused button. Pause freezes the needle; switching tabs pauses automatically.

The animation is the timing challenge itself. Sound starts off and is optional. This is a timing game, not a measurement of medical reaction time.

What makes a good run?

A caught lock earns 100–300 points based on how close you are to the center. Consecutive catches add a multiplier in steps of 0.2, up to ×2. A miss costs one life and resets the chain. Each lock allows 9 active seconds; a timeout counts as a miss.

Do friends get the same challenge?

Yes. A challenge link includes a course seed and your score. Opening it selects the same sequence of rounds, even on another day. Daily courses use the UTC date at the start of a run. Practice creates a fresh course. Scores are editable URL values, not verified leaderboard entries.

Where are my records stored?

Your latest twenty completed runs stay in this browser. No account, tracking code or server score submission is used by this game. Scores from different courses can vary in difficulty. The local best combines your saved courses.

Built for ArcadeBloom with AI-assisted code generation. No AI model runs during play. Game details and licence.