Where No Snake Has Gone Before
(Published on 13. July 2022, 20:43 by Nordy)
Collaboration with filuta. If you have not solved filuta’s puzzles, I highly recommend that you do! Especially this one (which was just featured on CTC!)
This collab started with filuta’s idea of a snake that travels outside the grid, and resulted in a puzzle that we think is pretty neat :) Many thanks to Piatato and henrypijames for testing. Difficulty estimated at 3½ stars. Enjoy!
Rules:
11x11 grid with 9x9 Sudoku: This puzzle is an 11x11 grid with a normal 9x9 Sudoku centered inside. Within the 9x9 Sudoku grid, normal Sudoku rules apply: place the digits 1 to 9 in every row, column, and 3x3 box.
Oddly Unconstrained Snake:
- Draw a snake (non-looping, non-branching 1-cell wide path of orthogonally connected cells) that may touch itself diagonally. The two ends of the snake are given as large white circles.
- Within the 9x9 Sudoku, all of the odd digits (and none of the even digits) belong to the snake.
- The snake may appear in any cell within the 11x11 grid, and may move in and out of the 9x9 Sudoku as necessary. Cells outside the 9x9 Sudoku have no numerical value—they exist only for the snake.
Standard Kropki—No Negative Constraint:
- Digits separated by a white dot must be consecutive.
- Digits separated by a black dot must have a ratio of 2:1.
- Not all dots are given.
Example: Below is a 6x6 example puzzle that you can solve online (Penpa, F-Puzzles, CTC).
Solve Online:
- CTC (or Intergalactic version)
- F-Puzzles (or Intergalactic version)
- Penpa+ (answer check on blue Sudoku)
Solution code: The nine digits in Row 2 of the Sudoku (from left to right)
Comments
on 15. August 2023, 18:25 by yttrio
Excellent puzzle, both in snake construction and figuring out the final digits!
on 31. January 2023, 18:01 by Christounet
Finally got that snake to travel properly around that grid ! It was funny to see how the clues worked multiple times during the different phases of the solve. Quite an achievement to make that work ! Thanks.
on 9. September 2022, 21:52 by Samish
The magic happens in this puzzle ! The different steps of the solve work very well together, great fun to solve. It felt on the easier side of 4/5 for me (but I always struggle with snakes)
on 15. July 2022, 16:16 by Jesper
Great puzzle, thanks!
on 14. July 2022, 01:26 by RJBlarmo
Great puzzle! Lots of fun and challenging bits of logic in the mid-solve for me.
on 14. July 2022, 01:18 by Piatato
What a tremendous snake! :-O I had a great time testing the puzzle, thanks for this fun invention!
on 14. July 2022, 01:13 by Nordy
Solution code and Penpa link fixed
