Futoshiki

Rooted in Japanese puzzle tradition, Futoshiki takes the logic of number placement and sharpens it with inequality constraints that force you to think in relationships rather than absolutes. Every row and column must contain each digit exactly once — but the greater-than and less-than signs wedged between cells narrow your options in ways that can feel either clarifying or maddening, depending on where you start.

Three difficulty settings shape how many constraint signs are given upfront. Harder grids offer fewer clues, leaving wider stretches of ambiguity that demand careful deduction before a single number can be placed with confidence. The moment a chain of logic clicks into place and cascades across the grid is genuinely rewarding.

The interface stays clean and unobtrusive, letting the puzzle itself do the work. No timers breathing down your neck, no cluttered menus — just a grid, some inequality markers, and however long it takes to crack it.