Threads. Every pair joined.
Every number has a partner. Draw a thread between them, square by square, and let no two threads share a square. Take your time.
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How to play and save
Draw a thread by moving from one square to the one beside it. Going back over a link takes it away again. A square may carry one thread only, and a number is the end of its own thread, never the middle of another.
On the wider boards every square must end up used. On the smaller ones a square may be left empty, so an unused square is not a mistake.
Arrow keys move the cursor. Shift with an arrow draws a link in that direction and carries the cursor along, so a thread runs outwards as you hold it. Direction buttons do the same and say why a join is refused when it is.
A finished board earns 100 points. Links drawn counts the links you made, including ones you later took back out. Your best active time is compared only on the same board. There is no countdown.
This Playroom is running without accounts, so there is no sign-in here. Your games and results are kept in this browser, on this device.