Yin Yang Sum Frame Sudoku
(Published on 21. December 2025, 21:10 by flutchman)
edit: apparently it's perhaps just a bit easier :)
Rules
• Normal sudoku rules apply.
• Yin Yang: colour the grid using two colours, such that all cells of the same colour are orthogonally connected, and no 2x2 area is fully one colour.
• Sum Frame: outside clues give the sum of the first three digits seen from that direction.
• Yin Yang Sum Frame: each Sum Frame clue only sees digits of one Yin Yang colour, while digits of the other colour are completely meaningless for that clue.
Which colour corresponds to each clue must be determined. (Each clue sees at least three digits of its color.)
Note: you may place colours or labels outside the grid to assist your solve. Those won't interfere with the solution checker.
Have fun and keep flutchin'.
Yours, Dying Flutchman
Please click the image to solve.
If you like this puzzle, you might be interested in the earlier ones from the Yin Yang series as well.
Yin Yang Skyscrapers
Yin Yang X-sums
Yin Yang Sandwiches
Yin Yang FSOE
Solution code: Row 5.
Enter 9 numbers, with each switch in yin yang colour indicated by a * (e.g. 12*3456*78*9)
Comments
on 3. January 2026, 00:40 by virus_dave
Very very fun, but I effectively had to bifurcate at the end of the shading to get the last few cells correct. I'm sure I missed something.
Break in was satisfying, I must say.
on 1. January 2026, 16:09 by glum_hippo
If this puzzle could be any more perfect, I do not know how.
==
Perhaps a dancing hippo in the background would make it better :)
Thanks for your high praise, much appreciated and blush-inducing although I do not quite agree.
on 1. January 2026, 11:18 by SparkNights
The wording of ruleset is misleading. It may let you think each clue outside the grid has 1 of 3 types: Shaded, Unshaded, Uncolored(The first 3 cells in the whole row/column, regardless of its color) I'd recommend you to merge 3rd and 4th point: outside clues give the sum of the first three digits of one Yin-Yang color seen from that direction.
==
Thanks for your suggestion. I hadn't considered that this could be a bit confusing. But now that you mention it, it's hard for me to 'un-see' the problem.
I've changed the wording above.
DF
on 23. December 2025, 16:48 by Exigus
A mind-taxing joy to solve. Thanks!
on 22. December 2025, 22:15 by thoughtbyte
Excellent, thanks!
on 22. December 2025, 21:09 by War
Beautiful 3* challenge! Thank you for setting
on 22. December 2025, 19:41 by GoodMorningCallum
A lovely construction with some fun logic - really enjoyed it. Thanks!
on 22. December 2025, 14:07 by Franjo
Gorgeous setting! Thank you very much for creating and sharing this wonderful YY-hybrid.
on 22. December 2025, 13:39 by Deckatron
I loved how the center region came together, very nice puzzle
on 21. December 2025, 22:47 by mellowrobinson
Beautiful construction!
