Sea Shells (YY)
(Published on 16. October 2025, 18:04 by Jolly Rogers)
RULES:
- Normal Sudoku rules apply.
Yin Yang: Divide the entire grid into Sea cells and Sand cells such that;
- All Sea cells are orthogonally connected.
- All Sand cells are orthogonally connected.
- No 2x2 area is fully Sea or fully Sand.
German Whispers: Any two Sea cells which share an orthogonal edge must differ in value by at least 5.
Sea Shells: Sea shells only appear in Sea cells and their digit counts the total number of Sea cells seen in all of its indicated directions combined (not including itself). NB: Sand cells do not block its view.
Crabs: Digits joined by a crab must sum to 10.
Example Puzzle of the Sea Shell rule:
Hope you enjoy!
Solution code: All Sea cells in Row 3 and Row 5
Comments
on 22. October 2025, 02:17 by virus_dave
Very fun puzzle, and generally pretty smooth once i was able to parse the tongue-twisting ruleset ????
Only got slightly stuck once. Some very cool deductions used throughout.
Thanks for setting!
on 19. October 2025, 14:27 by Exigus
Excellent clues, lovely puzzle. Thanks!
on 19. October 2025, 04:06 by ordnanceordinance
Really beautiful and unique puzzle. I got hard stuck yesterday and couldn't figure out where I'd made a mistake. Tried again with a fresh brain and was able to get it. Very fun.
on 18. October 2025, 00:47 by reformist
What a great interaction between the constraints! Took me a while to get going, but as soon as I did, it was a nice and consistent path from one "aha" to the next. Great puzzle.
on 17. October 2025, 21:49 by Jolly Rogers
Thank you for the warm comments, this is my first time setting a YY puzzle :)
on 17. October 2025, 21:24 by GreazeBull
Thank you for such a great puzzle
on 17. October 2025, 19:31 by VitP
uses a completely different strategy than all previous yy puzzles
on 17. October 2025, 17:09 by VitP
sea shells in sea cells off the sand's shore
yo ho ho and a bottle of rum
i could not resist
on 17. October 2025, 17:04 by VitP
i bet you could make a bunch of people RUN to try this puzzle if you made it clear up front that it's yin/yang
on 16. October 2025, 22:12 by VicJameson
I'm still quite new with yin-yang puzzles, but the german whisper rule made it very approachable. A lot of fun to solve, and fun to say 'sea shells see sea cells down by the sea shore'. Thanks very much!
