Logic Masters Deutschland e.V.

When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth.
— Sir Arthur Conan Doyle, The Case-Book of Sherlock Holmes

• Normal Quattroquadri rules apply: Place the digits 1-9 in each 3x3 box so they do not repeat in any box, row, or column.
• Dynamic Fog: Most of the grid is covered in fog. Placing a correct digit may do nothing, or it may clear some fog somewhere in the grid, possibly revealing other clues. No guessing is necessary. When the puzzle is complete, all fog will be cleared.
• Killer Birthday Cages: Digits in cages do not repeat, and sum to either 1 or 12. The solver must determine the sum of each cage.
• Renban: Digits on a pink line form a consecutive set of digits in any order. All renban lines move orthogonally and are 3 cells long.