Sunday Stumper: Slitherlink (Cipher; Even Rows/Columns) by John Bulten
This year, we have started to have 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 fourth Sunday Stumper is a Slitherlink puzzle with two variant rules added to it.
or solve online (using our beta test of Penpa-Edit tools; in default edgexoi mode: left-click+drag draws line, right click marks X on edge, clicking inside a cell alternates color to yellow then green then white; hitting tab will alternate to a number entry mode that can be used to write over the letter clues and hitting tab again will go back to edgexoi.)
Theme: From Here to Maternity
Author/Opus: This is the 78th puzzle from our contributing puzzlemaster John Bulten.
Rules: Standard Slitherlink rules. The letters A, M, O, and Y stand for different digits from 0 – 3. Also, an even number of cells in each row and in each column must be inside the loop.
Difficulty: 4.5 stars
Time Standards (highlight to view): Grandmaster = 17:30, Master = 25:00, Expert = 50:00
Solution: PDF; a solution video is also available here.
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.