Logic Masters Deutschland e.V.

Hello, solvers! I'll be quite busy in coming months and my puzzle release speed may slow down significantly. Therefore, I decided to share some harder puzzles. I'm so sorry that, for this puzzle, I've borrowed the ruleset from Flinty, whose Dutch Flat Mates series is highly recommended to check!

Rules:

• Squishdoku: Place digits from 1-9 in every cell, so that no digit repeats in a row, column, or 3x3 region.The dashed lines indicate the boundaries of regions, and cells on the lines are simultaneously part of the regions on both sides of the line.
• Dutch Flat Mates: Every '5' in the grid must have a '1' directly above it or a '9' directly below it. It may have both, but doesn't need both. However, There's exactly one '5' making things upside down, and thus having a '9' directly above it or a '1' directly below it (or both).
• German Whisper Lines: Adjacent digits along a green line differ by at least five.

Play on SudokuPad

Er, to be honest, I'm not very sure about the etiquette of reusing custom rulesets created by well-known setters, for example, the Rat Run. As a non-native English speaker, it's not very convenient for me to contact with the community. So please feel free to leave a comment here if you have any guidance, and I'll try my best. Sorry for any language improperty. Also, if Flinty feels uncomfortable with my use of the DFM rule, I'll delete this puzzle immediately.