Logic Masters Deutschland e.V.

Rules:

Normal sudoku rules apply.

Doublers: If a digit within a box is equal to its relative position in that box (read from left to right and top to bottom), the value of that digit is doubled for the Whispering Neighbours constraint. Each digit from 1-9 is doubled exactly once, and each row and column must contain exactly one doubler. Boxes may contain zero, one, or more than one doubler.

Whispering Neighbours: Each cell in the grid has at least one orthogonally adjacent cell such that their values differ by at least 5.

Gated Communities: Orthogonally adjacent cells that are separated by a cage border have values that differ by less than 5. Digits and values may repeat inside a cage. Cages cannot be divided into smaller cages.

The grid is covered in fog, which will clear completely after certain digits are placed correctly.

Links:

SudokuPad (includes solution check)

Solution Guide (pdf)

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Note: this is not a typical Fog-Of-War puzzle. The fog was added to help you focus on the first deduction. After the initial step, the entire grid will be revealed.

FischmitFahrrad and I have been exchanging ideas about sudokus with a 'global whispers constraint'. It became a wonderful collaboration, inspiring both of us to each create a puzzle; the companion sudoku by FischmitFahrrad (different ruleset, different solution) can be found here. Enjoy!

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