This is my first puzzle. I tried combining as many line rules as I could while maintaining the symmetry until... it had to be broken! Hope you enjoy it!
Solve on SudokuPad
Puzzle:
1. Normal sudoku rules apply.
2. Arrows: Numbers along an arrow must sum to the number shown in the circled cell, and may (or not) be repeated along the arrow.
3. GREEN - German whispers: Adjacent numbers on this line must have a difference of 5 or greater.
4. ORANGE - Dutch whispers: Adjacent numbers on this line must have a difference of 4 or greater.
5. LIGHT ORANGE - Entropic lines: Any set of three sequential cells along this line must contain a low (1-3), middle (4-6), and a high digit (7-9).
6. TEAL - Modular line: Any set of three sequential cells along this line must contain a digit from each of the 3-modular sets (1,4,7), (2,5,8), and (3,6,9).
7. DARK-YELLOW - Nabner: Digits on this line cannot repeat, and if a digit appears, then the digits consecutive with it must not appear.
8. MAGENTA (thick) - Renban: The set of numbers on this line must be consecutive. However, they may appear in any order, and cannot be repeated.
9. GREY - Palindrome: If a number appears as the Xth cell from one end of a palindrome, it must appear as the Xth cell from the other end.
10. BLUE - Twin region sum lines: Digits have an equal sum within each box the line passes through. Both lines that appear in box 3,6 and box 4,7 have the same sum value.
11. PURPLE (thin) - Maximal Symmetric Zipper: Digits equidistant from the line's center must sum to the same value. If symmetrically extended with respect to its center on both ends (boxes 4 and 6), it breaks the zipper condition; e.g, growing the zipper line to cells r4c2 and r6c8 (its symmetric) breaks the zipper condition (r4c2+r6c8 is different than the zipper line sum value).
Solution code: Row 1, digits left to right.
on 11. November 2025, 22:22 by Ikke Moon
The SudokuPad links to a slightly different puzzle on the app. Plus, I'm colour-blind :-(
on 11. November 2025, 17:54 by robertolosada
Added clarification that the zipline can only be extended from its ends, which lie in boxes 4 and 6.
on 11. November 2025, 08:10 by robertolosada
It is true that the "maximal" is not necessary, but I reckon that speeds up everything considerably.
on 11. November 2025, 07:18 by jordanza
The "maximal symmetric zipper" was unnecessary. It can be solved with normal zipper in mind.
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