How to play
Fill each row, column, and 3×3 box with 1–9.Select an empty cell, then use the number pad or keyboard. Pencil mode records possible numbers; Erase clears an entry. Check highlights duplicate numbers in a row, column, or box. Hint fills one correct number, but an assisted run does not count toward your best time.
Every new puzzle is generated with exactly one solution. Difficulty controls clue density; individual puzzle difficulty varies.