Logic Masters Deutschland e.V.

I set this puzzle several months ago but forgot to upload it here.

• Standard sudoku rules apply: The digits 1 through 9 appear in every row, column, and box.
• Diagonal Sums: Each nice clue outside the grid shows the sum of the digits along the indicated diagonal. Digits may repeat if allowed by other rules.
• Quadruples: Nice digits (6 and 9) in a white quadruple circle must be placed at least once in the four cells touching that circle.
• Nice Pairs: Digits in cells connected by a ♋︎ symbol have a nice sum (6 or 9). Not all possible ♋︎s are necessarily given.

Play in SudokuPad