Regional Yajilin Sudoku
(Published on 7. December 2024, 12:23 by Myxo)
This puzzle is a combination of Irregular Sudoku, Regional Yajilin and Fortress. I opted to go for a minimal grid without given digits, thus the Irregular Sudoku is quite challenging. Enjoy!
Rules:
Irregular 0-8 Sudoku: Place the digits 0-8 exactly once in each row, column and region.
Regional Yajilin: Shade some cells of the grid such that no two shaded cells share an edge. Draw a single closed loop (without intersections or crossings) through all unshaded cells. A digit in a circle indicates the number of shaded cells in that region.
All circles must contain different digits.
Fortress: Digits in shaded cells must be greater than any of their orthogonal neighbors.
Solution code: row 6
Comments
on 29. June 2025, 14:59 by Qodec
Can't believe how well this resolves. Very impressed.
on 29. June 2025, 12:56 by wisty
Really cool construction, but damn, fortress is hard. I suspect some of the irregular techniques and short chains I used weren't remotely necessary, if I'm to believe Oneill's comment that it was smooth for them xD
on 21. January 2025, 01:57 by petecavcc
very nice and very hard!
on 13. December 2024, 20:26 by rmm466ss
Wonderful puzzle! The irregular grid was perfect for this variant.
on 11. December 2024, 12:37 by MagnusJosefsson
Great puzzle, very enjoyable!
on 10. December 2024, 13:38 by madhupt
The Yajilin part was straight enough but the sudoku part was really tough, but only up to a point after which the puzzle really unfolded. Thanks for sharing this.
on 8. December 2024, 11:43 by Piatato
Very impressive construction! The sudoku part went a bit more slowly for me than the yajilin, but it was all fair and interesting!
on 7. December 2024, 16:13 by Dragonslayer
Yajilin part is very easy. Irregular+fortress part is full of tricks and is pretty good!
on 7. December 2024, 14:25 by ONeill
Cool! the irregular was pretty smooth for me :)
on 7. December 2024, 12:47 by dumediat
Lots of fun, incredible that this resolves uniquely! :)
