Logic Masters Deutschland e.V.

♫ as we lie, wet and soft, with linked limbs / and your knees make the hinge, we are left with: / a melt-in-mouth thing... ♫

Two things need addressing, because I say they do. First: the entropic lines are yellow (as opposed to gold, peach or orange) because it was the colour most readily available when I made a quick, mustn't-forget-this sketch of the puzzle's main idea, and when I realised I could extend my streak of puzzles named after songs if I kept it, any desire I may have had to comply with the meta simply vanished. Second: if you were to ask me why I've opted for an unconventional disambiguator clue, as opposed to an arrow, a black Kropki dot or a stand-alone killer cage, I would scream. A more articulate answer would enter spoiler territory very quicky, but basically, it's me saying "please keep your solve inside the logical path at all times" in a way that should serve to minimise misdirection. It's not too disruptive visually either, which is a thing I can't pretend I don't care about. Anyways, that's everything covered, so as I always wind up saying, good luck and happy solving!

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Rules
Normal sudoku rules apply.
Adjacent digits along green German Whispers lines must differ by at least five.
Along yellow Entropic lines, each set of three connected cells must contain one low digit (1, 2 or 3), one medium digit (4, 5 or 6) and one high digit (7, 8 or 9), though these may appear in any order.
The sum of the digits in one of the caged dominoes is double the sum of those in the other.

You can solve using f-puzzles or, a first for me, in the CTC app with solution checking! Wonders may never cease! Also of note: I have the additional script for f-puzzles that adds Renban and German Whispers to the constraints list (courtesy the briliant Rangsk), so in that version there are real German Whispers lines hiding beneath the cosmetic green ones. Well, not if you don't have the script as well, of course, but they seem to persist if you do, which is rather neat. By contrast, the CTC one, being just an export of the f-puzzles version, hasn't got a clue what any of the lines mean, but at least it draws them behind the grid...