Logic Masters Deutschland e.V.

Special Thanks
aqjhs has already released two tessellation puzzles with the Flat Mate rule, one with Dutch Whispers, another with Palindromes. And it was aq that helped me discover a lot of logic used in this puzzle, even providing a very clean 'unique' parity draft (that 'probably' isn't humanable), but allowed me to work through logic with some help from goodcity to agree what is a fair 3/5 difficulty level deduction..

I might have gone a bit overboard with the hints below, but as this is quite out of the ordinary, it might help people find the tricky logic in an unfamiliar puzzle type.

Previous Dutch Flat Mate Puzzles
This has been a weekly series since '18 Oct 23'. Here is a spreadsheet link for all the previous puzzles in the series, which also has a few teasers for upcoming constraints/guest setters in the series (subject to change).

This alternative link offers a limited LMD search for Dutch Flat Mates.

To play the puzzle, please click the image:

Initial Setter Difficulty: 3 / 5

Tessellation Rules
- Place digits from 1-9 in each square and octagonal cell.
- Cells sharing an edge can't have the same digit.
- Each horizontal row and vertical column contains a non-repeating consecutive set of digits in any order.

Dutch Flats
Every 5 in the grid must have a '1' directly above it or a '9' directly below it. It may have both, but it doesn't need both.

Parity Lines
Adjacent digits along a red line must have different parity.

Hint to start

There is a global appreciation on Happy 5s.

Above hint expanded

5s by Flat Mates can't appear in C1, C2, C8, C9, without breaking the 'renban' like rules found in Tessellation puzzles. Happy 5s need extreme digits, which heavily restricts those renbans.

Hint to make the next step easier

Hopefully one of your early digits is a 7 in Row 8. That 7 does some strong work by tessellation rules.

Guest Setters
Two weeks of guests, including a whole half a puzzle from someone making their Flat Mate debut!
Next week, it's 01100100 01100001 01101101 01101111 sorry Damo, I'm not sure what came over me there...
... and then the week after sujoyku, who appears more than 'Periodically' on the series, 'Summing' up something cool with series debutant Sotehr!