Logic Masters Deutschland e.V.

Rules:

Standard Sudoku rules apply: Each row, column, and 3×3 box must contain the digits 1 to 9 exactly once.

Upward-pointing arrows (↗, ↖) indicate diagonals where all digits must share the same parity — that is, all digits must be either odd or even. The parity may differ between arrows and must be determined by the solver.

Downward-pointing arrows (↘, ↙) indicate diagonals that follow the rules of either a German Whisper line or a Slow Thermometer, starting from the arrow tip. The applicable rule may vary between arrows and must be deduced by the solver.

German Whisper line: Consecutive digits along the line must differ by at least 5.

Slow Thermometer: Digits must be non-decreasing, starting from the bulb (i.e., the arrow). Each digit must be greater than or equal to the previous one.

Puzzle can be played online here: Archer's Dozen