JS Whisper Yin Yang
(Published on 3. January 2026, 02:10 by yttrio)
Rules:
Normal Sudoku rules apply.
Yin Yang: Shade some cells such that all shaded cells are orthogonally connected, all unshaded cells are orthogonally connected, and no 2x2 area is fully shaded or fully unshaded.
The shaded cells act as a German Whispers line: if two orthogonally connected cells are both shaded, then the digits in those cells must have a difference of at least 5.
Japanese Sums: Clues outside the grid give the sums of shaded cell segments in the respective row or column, in order, where unshaded cells separate segments. A question mark indicates any digit from 0 to 9, but no clue may have a leading zero. An asterisk denotes an arbitrary number of Japanese sum clues. This could be zero, one, or multiple.
Solution code: Digits in shaded cells in row 3 (left to right) followed by digits in shaded cells in row 8 (left to right)
Comments
on 12. January 2026, 18:36 by QuintusScaevola
Thank you yttrio for answering my question and for setting this beautiful puzzle. It was very neatly solved once you clarified the reading order of the Japanese sum clues with some tricky, but beautiful logic mid to late solve for a smooth finisher. Spectacular!
on 12. January 2026, 03:39 by waffles_the_dog
Wonderful puzzle, I really liked the break in and all the logic flowed really nicely from there (though I still found it quite hard :D )
on 11. January 2026, 10:11 by QuintusScaevola
I have probably a stupid question... What's the reading order of the clues outside the grid? It says in the rules that they apply "in order", but e.g. in row 6: does the single ? apply to the first or second shaded segment? Or similarly in column 8: is the reading order top -> down? Both options seem fine for me, with the logic being that the clues are labelled in the order closest to their respective border.
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Not a stupid question at all if you're not familiar with Japanese sums :)
It goes in reading order. So for clues on the left side, the left clue corresponds to the left-most set of shaded cells (in row 6, the ?? is the left set and the ? is the right set). For clues on the top side, the top clue corresponds to the top-most set of shaded cells.
~yttrio
on 4. January 2026, 11:12 by Piatato
Neat!
on 4. January 2026, 08:52 by KNT
impressive!
on 3. January 2026, 16:59 by marcmees
impressive puzzle. Thanks fo sharing.
on 3. January 2026, 16:41 by Christounet
Tough ending for me! Cool that it works with only question marks. Thanks :)
on 3. January 2026, 16:40 by Franjo
Brilliant setting - as usual. With all these ??? it has a RockyRoer-look ;-)
Thank you so much for creating and sharing another wonderful YY-masterpiece.
on 3. January 2026, 15:28 by thoughtbyte
Best Yin Yang of recent memory, awesome stuff. Thanks!
on 3. January 2026, 14:28 by Mr. Happy
Fantastic!
on 3. January 2026, 13:32 by Exigus
That was brilliant. Tricky mid-game but well worth it. Thanks!
on 3. January 2026, 11:37 by Snookerfan
Beautiful puzzle with a very tricky midsolve! Thanks
