Logic Masters Deutschland e.V.

Collaboration with Dorlir.

I shared a weird idea with Dorlir, and he brought it to life with just 5 clues. The rules shouldn't be too complicated, but rereading them may be helpful in getting unstuck. Difficulty estimated at 4.5 stars.

Rules:

Chaos Snakes: Place the digits 1 to 9 in every row, column, and region. Every region is a snake—a one-cell wide path of orthogonally-connected cells that does not branch or touch itself orthogonally.

Dutch Whisper Snakes: Some of the regions are Dutch Whisper snakes—within a Dutch Whisper snake, orthogonally-adjacent digits must have a difference of at least 4. Different Dutch Whisper snakes must not touch each other, not even diagonally.

Row/Column Whisper Sums: Cells with diamonds are on the Dutch Whisper snakes. A digit in a diamond gives the number of snake cells (including itself) that it sees either in its own row or its own column, with region borders obstructing vision (a digit in a diamond may see cells in the other direction, but those cells are not counted toward the total). The number in the top-left corner gives the sum of the digits that are seen in that corresponding row/column. A snake may contain more than one diamond.

Clarification: a digit in a diamond may see the same number of cells in both its row and its column, but the total (sum) need only apply to at least one of them (not necessarily both).

Example:

Here is an example of valid rule interactions. The two regions below are each Dutch Whisper snakes—adjacent digits differ by at least 4. The regions do not touch each other orthogonally or diagonally. The 6 in R1C4 sees six cells in its row, and the sum of those six cells is 28. The 3 in R2C6 sees three cells in its row, and the sum of those three cells is 17 (the cell in the column does not contribute to the count nor the sum). The 4 in R3C4 sees four cells in its column, and the sum of those four cells is 19 (the 4 also sees four cells in its row, but those cells do not necessarily sum to 19 since the diamond clue has already been fulfilled by the cells in the column).

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