Normal sudoku rules apply.
Palindromes - Gray lines contain digits that read the same in either direction.
Region Sum Lines - Blue lines are split by the region boundaries into segments that have the same sum.
Maximum - Cells with arrows pointing outward are greater than their neighbors.
Ambiguous Kropki Ratios - Digits separated by a gray dot are in either a 1:2 or 1:3 ratio. Not all possible dots are given.
German Whispers - Digits separated by a green dot must differ by at least 5.
Solution code: Row 1
on 4. January 2026, 20:23 by Inge
That was hard, but lot of fun, thank you