Sunday Stumper: Slitherlink (Switch) by Matej Uher
Since 2021, we have posted some extra difficult Sunday Stumpers, about once a month. These will be quite tough puzzles, but with a logical path to be found (and solution videos to help). This ninth Sunday Stumper of 2022 is a Slitherlink (Switch) puzzle by Matej Uher, author of our new Slitherlink and Variations 2 book. Each clue here has to switch with one of its orthogonal neighbors, so it will be quite a challenge to find the complete loop.
(view directly for a larger image)
or solve online (using our beta test of Penpa-Edit tools; use tab to switch between edgex mode where left click+drag draws lines and right click marks X’s, and a shading and number entry mode to mark/update the switched clues.)
Theme: Knight’s Moves
Author/Opus: This is the 5th puzzle from guest contributor Matej Uher.
Rules: Standard Slitherlink rules. Also, each given clue has to switch its initial position with one of its adjacent neighbors.
Also, see this example:
Difficulty: 5 stars
Time Standards (highlight to view): Grandmaster = 30:00, Master = 45:00, Expert = 1:30:00
Solution: PDF and solving video.
Note: Follow this link for classic Slitherlink and this link for Slitherlink variations. If you are new to this puzzle type, here are our easiest Slitherlink puzzles to get started on. More Slitherlink puzzles can be found in The Art of Puzzles, Slitherlink and Variations, and our beginner-friendly book Logic Puzzles 101.
So crazy ! 3h spanned over 3 days, with a little help from the walkthrough to get the bottom start, and an error at the very end of the solve, caused by rushing the ending, and fixed by checking the solution…
The most stumping stumper for now in my opinion