Logic Masters Deutschland e.V.

For an easier 6x6 introduction to this rule, see my earlier puzzle Constraint Selectors.

Normal Sudoku rules apply.

Every line has a Constraint Selector. If the digit on it is high (6, 7, 8, 9), the high (top) constraint applies to the line. If the digit is low (1, 2, 3, 4), the low (bottom) constraint applies. A 5 never appears on a selector.

The constraints are standard:

• Pink (REN): Renban line. The digits on such a line form a non-repeating consecutive set in any order.
• Black (DBL): Black Kropki line. Adjacent digits have a 1:2 ratio (one is double the other).
• Teal (MOD): Any run of three adjacent cells must contain digits from each of the three modular sets {1 4 7}, {2 5 8}, and {3 6 9}.
• Red (PAR): Parity line. Adjacent digits have opposite parity (one is even, one is odd).
• Gray (INC): Thermometer. Digits strictly increase when moving away from the selector.
• Green (GW): German Whispers line. Adjacent digits differ by at least 5.
• Beige (FAC): Factor line. Among adjacent digits, one divides the other.
• White (CON): White Kropki line. Adjacent digits are consecutive.

For the avoidance of doubt: The selector is part of the line and does not split the line in two.

Play on SudokuPad

No generative AI tools were used in the preparation of this puzzle or its presentation, nor in any of my puzzles.