Ichikara (Pack 1)
(Published on 7. August 2025, 10:16 by juggler)
Thanks to everyone who provided ideas and suggestions, especially Andrewsarchus and Crusader.
ICHIKARA
• Divide the grid into regions. A region contains the numbers from 1 to N once each, where N is the largest number in the region.
• "?" stands for any number.
• Regions may also contain empty cells.
Solution code: In each puzzle, the leftmost digit in the topmost row of the region occupying the lower right corner of the grid.
Comments
on 15. January 2026, 09:30 by just_ham
I enjoyed this pack a lot! The logic was very satisfying to break through.
on 9. January 2026, 01:23 by dzamie
That's a neat puzzle. Puzzle 4 made me feel rather clever for figuring out the ? value.
on 18. December 2025, 13:27 by eap314
I love the logic throughout. This is a very nice concept; I might try to make a cc or something based on it.
on 3. September 2025, 08:12 by SudokuExplorer
Really enjoyable concept and little treats, thanks!
on 29. August 2025, 20:16 by damasosos92
Beautiful introduction. I'm convinced, will try the others!
on 8. August 2025, 19:31 by blackjackfitz
Really liked this, looking forward to seeing what else you do with this ruleset.
Took me a minute to get my head around it but then it all clicked pretty nicely. I agree with RockyRoer, either I got much better at this or the 4th puzzle is much easier than the others.
on 7. August 2025, 22:04 by Kiwo
This is really clever! Very beautiful puzzle, thank you for sharing.
on 7. August 2025, 17:34 by juggler
(Penpa+ links)
on 7. August 2025, 17:32 by wuc
That was awesome fun to find rules for such a new kind of puzzle. Very refreshing. Looking forward to more of these maybe a bit harder? Maybe combined with any cc constraint?
on 7. August 2025, 14:05 by sfushidahardy
Very cool!
on 7. August 2025, 12:50 by RockyRoer
Very fun. Either I was learning, or #4 was easiest, or both :-). Thanks for setting and sharing them with us.
on 7. August 2025, 12:25 by Franjo
Nice twist on Nikoli‘s old Block Puzzles! Thank you very much for creating and sharing.
on 7. August 2025, 11:50 by Qodec
OK I'm sold, would like to solve more.
