Fill every node with a number from 1 to the size of the board. Each number appears exactly once in every row and every column, and every bond must be true.
A bond is a thick strut with a badge. The badge shape tells you the family: chevrons compare, circles add, rounded boxes subtract, diamonds multiply or divide, pips are about even and odd. A strut with no badge says nothing. Tap any badge in the game to read its rule.
1 star for solving, 1 for no mistakes, 1 for beating the par time shown above the board. Any hint limits the level to 1 star.
Yes. Every level is checked by our solver, which solves it like a person (one logical step at a time) and proves there is exactly one answer.
A hint first shows where to look and which step to use. Tap "Why?" for the reasoning in words, and "Show me" to place the number. All three parts cost one hint. You get one free hint every day.
They show the hardest step needed: Easy (singles and bond checks), Medium (pairs), Hard (bond claims: a bond that must use a number blocks it from the rest of the line), Expert (triples) and Master (one what-if step).
If every pair of numbers that can fill a bond contains, say, a 4, then the 4 of that row (or column) must sit on the bond. No other node in the line can be 4.
The game's currency. You earn them from new stars, the Daily, the Weekly, chests and achievements, and spend them on hints.
Everyone gets the same grid each day (UTC). The clock runs on our server from the moment you open it until the board is complete. No hints. Fastest time wins.
Yes, with the level editor. The solver checks that your level has one answer and is not too easy before you can share it with the community.