Logic Masters Deutschland e.V.

Rules:

Normal Sudoku: Fill the grid with digits 1–9 such that every row, column, and 3 by 3 box contains each digit exactly once.

The Tenth Box: The nine center cells of the standard 3 by 3 boxes form a "Tenth Box" which must also contain the digits 1–9 without repetition.

Any rule or constraint in a standard 3 by 3 box is applied to the corresponding cells in the Tenth Box. Constraints map from the nine standard boxes to the Tenth Box, but not vice-versa.

Killer Cages: Digits in a cage must sum to the value in the top-left corner. Digits cannot repeat within a cage.

White Kropki Dots: White kropki dots sits between two consecutive digits.

Maximum: The digit in the gray cell is greater than each four orthogonally adjacent cells.

​Example: In this puzzle, the first, second, fourth and fifth cells in Box 1 are inside the cage of sum 17. This means that the sum of the digits in cells R1C1, R1C2, R2C1 and R2C2 is 17. Furthermore, the sum of the digits in the first, second, fourth and fifth cells of the Tenth Box (R2C2, R2C5, R5C2 and R5C5) is also 17.

Example: In this puzzle, the fifth cell in Box 5 is a Maximum Cell. This means that the digits in R5C5 is greater than the four adjacent cells. Furthermore, the fifth cell of the Tenth Box (R5C5) is also greater than the digits in R2C2, R5C2, R5C8 and R8C5.

Solve on Sudokupad

Tenth Box Puzzles:

• 1. The Tenth Box: Unboxing
• 2. The Tenth Box: German Whispers
• 3. The Tenth Box: Renban
• 4. The Tenth Box: Kropki
• 5. The Tenth Box: Dutch Whispers
• 6. The Tenth Box: Killer Cages