Colouring Book Greyscale Edition (Ambiguous Thermo/Palindrome)
(Published on 8. August 2026, 08:08 by damo_89)
I was in a bit of a setting slump so thought I'd have a go at setting a standard puzzle with standard constraints. The random constraint generator suggested thermometers and palindromes. However, looking at the grid I now can't work out which lines are thermos and which are palindromes; sorry about that. Good luck! Thanks to the testers; consensus difficulty was 3 to 4 stars.
- Normal sudoku rules apply: Place the digits 1 to 9 once each in every row, column, and 3x3 box
- Each grey line is either a thermometer or a palindrome, to be determined by the solver
- Thermometers: Digits along a grey line must strictly increase from one end of the line to the other
- Palindromes: Digits along a palindrome must read the same in both directions
Solution code: Column 8
Comments
on 13. September 2026, 00:32 by emoney1374
Awesome puzzle! Tried to solve without placeholder digits but needed to do so to solve. Great construction!
on 16. August 2026, 15:51 by ViKingPrime
Tougher than your average colouring puzzle, for sure.
on 15. August 2026, 18:42 by laky
1宫这里设计太出生了，漏看了，导致我看了两个小时
on 9. August 2026, 07:34 by Piatato
Excellent!
on 9. August 2026, 06:15 by blueberrypug
I agree with the 3.5
on 8. August 2026, 11:17 by Wuschel
Very nice, thank you!
on 8. August 2026, 10:41 by Elliott810
Brilliant puzzle! For me 3.5* difficulty. Thank you:)
