Logic Masters Deutschland e.V.

Normal sudoku rules apply: Put the digits 1 to 9 once each in every row, every column, and every 3x3 box.

Antiknight: Any two cells separated by a knight's move in chess cannot contain the same digit.

Antiking: Any two cells separated by a king's move in chess cannot contain the same digit.

Modular lines: Any three consecutive cells on a red modular line must contain digits with different remainders when dividing by 3. I.e. one digit must be from the set {1, 4, 7}, one from the set {2, 5, 8}, and one from the set {3, 6, 9}.

XV: Any two cells joined by an X must contain digits summing to 10. Any two cells joined by a V must contain digits summing to 5. Not all X or V are necessarity given (no negative constraint).

Kropki dots: Any two cells joined by a black dot must contain digits with a ratio of 1:2 (one must be double the other). Not all dots are necessarily given (no negative constraint).

Play in SudokuPad.