Pre-Christmas Special: Decorating the tree
(Published on 29. November 2025, 13:38 by SharpFox)
Before the Sudoku Advent calendar starts on 1 December, here is a festive bonus puzzle. A Christmas tree, a present and a few familiar Sudoku rules.
The Advent calendar is primarily intended for beginners to learn a few rules and solving strategies, but there will also be some specials that may be of interest to non-beginners. Especially on 6, 12, 21, 23 and, of course, 24 December.
SudokuPad
Rules:
- Normal Sudoku rules apply.
- Anti-King: Cells, that are a (chess) king's move apart, cannot contain the same digits!
- The green line (christmas tree) is a german whisper line. Adjacent digits on this line must differ by at least 5.
- The pink line (gift) is a renban line. It contains a set of consecutive digits in any order.
- The digits on an arrow sum to the digit in the attached circle.
- Digits strictly increase along a thermometer, starting from the bulb to the tip.
Have fun solving the puzzle and enjoy the first Sunday of Advent!
Solution code: The digits along the lower left German Whisper Line, starting from the top (SudokuPad copies it correctly, 7 digits):
Comments
on 4. December 2025, 22:32 by Nakedsinglehunter
Hat Spaß gemacht :)
on 30. November 2025, 13:44 by SennyK
Lovely puzzle, thank you for sharing :-)
on 30. November 2025, 09:08 by Cyprane
I also completely forgot about one of the rules and was stuck for a long time. Once I remembered, it was smooth sailing. Beautiful puzzle. Thank you.
on 29. November 2025, 18:32 by macintux
Unfortunately by the time I needed one of the rules, I had long since forgotten it was there and I was stuck for a long time. Very nice puzzle.
