Shishi (Ichikara)
(Published on 20. December 2025, 08:15 by The Book Wyrm)
Shintaro also gets further credit for testing this puzzle, and suggesting the name.
Note: This puzzle is very difficult, but it can be solved logically.
For easier puzzles with the same ruleset, some introductory puzzles (with an example) can be found here.
Rules:
- Divide the grid into orthogonally connected regions.
A region must contain the numbers from 1 to N once each, where N is the largest number in the region. - Regions may also contain empty cells.
- A ? stands for an unknown number.
Penpa link: Click Here
Solution code: For each row of the grid, the number of vertical region borders in that row.
Comments
on 18. July 2026, 10:58 by wisty
Jokes aside, this puzzle was incredible and novel and never gave up until the very end. I really enjoyed my time internalizing the implications of the setup, enough that there's an enthusiastic hidden comment about my approach.
on 18. July 2026, 10:52 by wisty
Best U-Bahn ever
on 26. April 2026, 05:25 by widjo
beautiful
on 23. December 2025, 16:51 by cyddrdrd
This is purely masterclass!
on 22. December 2025, 05:11 by MonsieurTRISTE
The fact this puzzle exists is a miracle.
on 21. December 2025, 14:42 by Andrewsarchus
Brilliant!
on 20. December 2025, 13:00 by sfushidahardy
Such a cool puzzle! It's different from anything else I've solved.
