Whirlpool
(Published on 18. February 2026, 17:42 by etoler)
Normal Sudoku rules apply.
[RS] Region Sum Lines: Box borders divide blue lines into segments with the same sum. Different lines may have different sums.
[GW] German Whispers: Adjacent digits along a green line must have a difference of at least 5.
Melding: Each line in the grid can be divided into two segments, each with a different rule as indicated on the line's ends. Each segment spans at least two cells. The point at which the segments meet is a single cell, to be determined by the solver.
XV: Digits separated by an X sum to 10.
Solution code: Digits in cells where line segments meet, from left to right.
Comments
on 26. February 2026, 12:35 by PancakePie
Beautiful and fun! Thank you!
on 24. February 2026, 13:26 by corrie
Surprisingly I found it to be much easier than initially assumed. Beautiful logic & beautiful visuals, one of my favorite Sudokus for sure!
on 24. February 2026, 09:22 by davidz32z
Really neat puzzle! One of the few that my partner saw me doing and said "oh that one looks fun!" Beautifully set, beautiful logic, and beautiful grid!
on 24. February 2026, 03:00 by MiguelMunoz
Thank you. Now the rule is clearer. With "overlap," the clue would have read "The point at which the segments overlap is a single cell…", seems like it would have made it clearer for me, but I'm not sure if it would work for everyone. Sometimes, describing a rule like this clearly is a different kind of puzzle.
on 23. February 2026, 22:37 by MiguelMunoz
"The point at which the segments meet is a single cell…" Does this mean that I should apply both constraints to that single cell? If so, then maybe the word "meet should be replaced by "overlaps."
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I used the word "meet" because if they were drawn as separate lines, they would touch in the center of that cell. To me, an overlap might imply that one line begins BEFORE the other ends, meaning multiple cells would be affected by both rules. But, I can see where if you're coloring the cells, then there is a cell where the colors "overlap" (i.e. it has both colors). The short answer, though, is that there is exactly one cell that is affected by one rule in one direction and the other rule in the other direction. -Erin
on 20. February 2026, 14:05 by JRaunak
Had a doubt, the melding cell will be a part of both lines, or none of the lines?
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It's part of both! - Erin
on 19. February 2026, 04:26 by etoler
Some major visual tweaks, because I'm incapable of leaving well enough alone. Thanks for the feedback so far, everyone!
on 19. February 2026, 02:24 by CarnacTheMagnificent
Determining the "Melding" cells was fun and interesting. Thanks for the puzzle.
on 19. February 2026, 00:07 by Exigus
A bit scary but not hard. Very nice idea and well executed. Thanks!
on 18. February 2026, 18:28 by StefanSch
Intresting rule set.
