Fill the grid so digits appear exactly once in every row, column and block. The classic logic puzzle. 🎚 Levels — new variant rules unlock as you climb: • L9 ⟍ diagonals: digits are also unique on both diagonals • L14 ♞ anti-knight: equal digits cannot be a knight move apart • L18 ⊞ hyper: 4 extra 3×3 zones with no repeats • L22 ≠ non-consecutive: side-neighbours cannot differ by 1 • L26 ♚ anti-king: equal digits cannot touch even diagonally • L30 ◩ even/odd: □ cell = even digit, ○ = odd • L34 ⧉ jigsaw: irregular blocks instead of squares 👑 Killer — the grid splits into cages: digits in a cage add up to the number in its corner and never repeat. 🆓 Free — a 6×6 or 9×9 board with no variants, your choice of difficulty.