Normal sudoku rules apply (1-9 without repeats in every row, column, box)
The purple numbers outside the grid are X-Sums (first X digits from that end of the column, where X is the first digit from that end of the column, add up to the sum). These are the 6 and 9.
The orange 0s on the outside of the grid are sandwich sums. They are the sum of the digits between the 1 and 9 of their rows, not including the 1 and 9.
Digits separated by a white circle have a difference of exactly the number within the circle
Digits marked in grey are identical to the digit on the opposite side of the grid. For example, R2C3 and R8C7 contain the same digit. This ONLY applies for the digits marked in grey.
The golden lines are nabner lines. Along a line, no two digits may be consecutive or identical.
The two nabner lines with the outlines each have the same set of digits.
Click the image for the solving tool
Lösungscode: Row 6, left to right
am 20. Mai 2026, 22:57 Uhr von PersonWhoExists50306
The thing about the nabners with the same set of digits is no longer marked as an additional hint
am 19. Mai 2026, 17:55 Uhr von Snookerfan
I solved the puzzle without the hint, which I only could by extensive case testing. There were some lovely steps, but incredibly hard to spot. The negative constraint is very powerful, but hard to scan. Maybe you should make the hint a rule to make the solve more pleasant, because after finding out that the nabner lines contain the same set of digits, the puzzle became really smooth and fun. Thanks
reply from PersonWhoExists50306: Noted. I have edited the rules description accordingly. Thanks for the feedback.