Logic Masters Deutschland e.V.

This puzzle combines kropki pairs with a negative XV constraint, i.e. adjacent digits cannot sum to 5 or 10. There is no negative constraint on black (or white) kropki dots.

I tried to keep this relatively simple by only using one negative constraint* and breaking up the coloring relatively early. Please let me know in the comments if you would like to see a more intricate version of this.

*most similar puzzles I've found also use negative kropki constraints.

Play online: CTC, Sudokulab

Rules

Normal Sudoku Rules

Place the digits 1 through 9 in each empty cell. Digits must not repeat within the same row, column, or box.

Anti-XV

Digits in adjecent cells must not sum to 5 or 10

Black Kropki Dots

A black dot between cells indicates cell values with a 2:1 ratio. Not all dots are necessarily given.