Logic Masters Deutschland e.V.

---- RULES ----

Normal Sudoku rules apply: Fill the grid with digits 1 to 9 appearing once each in every row, column, and 3x3 box.

Whispering Loop: Draw a single 1-cell-wide loop of orthogonally connected cells into the grid. Different loop segments cannot touch, not even diagonally. The loop acts as a German Whispers Line. Adjacent digits along the loop must differ by at least 5.

Tetrominos: All cells (with the exception of the central shaded cell) that are not part of the loop must be part of a Tetromino, a group of four orthogonally connected cells. Tetrominos never cross box borders and different Tetrominos do not overlap.

Killer Sums: Cells with small numbers lie within a Tetromino (in any position). The digits within that Tetromino must sum to that number. Not all Tetrominos contain a Killer Sum clue.

Less-than-sign: The less-than-sign points towards the smaller digit.

---- LINKS ----

Solve this puzzle using SudokuPad

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This Sudoku is part of my series of "build-your-own-loop Sudokus". If you liked solving this puzzle or if you prefer other combinations of loop logic and constraints, feel free to give the other sudokus of the series a go too:

	Loop Logic	Loop Constraint	Further Constraints
Somedoku-Loop	Somedoku, Circles	Parity Line	Kropki Dots
Deconstructed- RSL-Loop	Deconstruction	Region Sum Line	Little Killers
Whispering-Sequence- Loop	Circles	Dutch Whispers	Kropki Dot
Fluisterende Loop	Star Battle	Dutch Whispers	Korpki Dots
Yin-Yang-Loop	Yin Yang	Region-Sum-Line	Korpki Dots
Entropic-Sequence- Loop	Circles	Modular Line	Thermometer
Find-the- Whispering-Loop	Arrows	German Whispers	-
Country-Road- Loop	Country Road	Parity Line	Irregular Sudoku
Modular-Sequence- Loop	Circles	Modular Line	Thermometer
Summing-Zipper- Loop	Counting Cells	Region Sum Line	Zipper Lines
Mid-Loop	Mid-Loop logic	Entropic Line	Kropki Dots
Whispering-Zipper- Loop	Counting Cells	Dutch Whispers	Zipper Lines
Super Bowl Loop	Oponents, out-of-bounce	Polarity Line	Kropkis, XV, Nabner, Zipper
Linesweeper Loop	Linesweeper clues	Parity Line	Little Killers
Modular-Zipper- Loop	Counting Cells	Modular Line	Zipper Lines
Balance Loop	Balance clues	Parity Line	Little Killers
Entropic-Zipper- Loop	Counting Cells	Entropic Line	Zipper Lines X-clues
Hiking-through- the-Fog Loop	Signposts	Dutch Whisper, Polarity Line	Kropki Dots X-clues
Renbanimo Loop	Pentominos Guiding Cells	Renbanimos	Kropki Dots Odd cells
Deceiving Loop	Wrogn Clues	Wrogn Clues	9 different constraints
Count-the- Whispers Loop	Counting Cells	German Whispers	Kropki Dot
Whisper-me- Sum-thing Loop	Line-sums	German Whispers	Kropki Dots
Road Running Loop	Road Runner	Parity Line	Kropki Dots
Magically Modifying Loop	-	Incrementers, Decrementers, Nullifiers	Magic Squares, Killer cages, Kropki Dots
Skiing Loop	Gates	German Whispers	Kropki Dot, Between Lines
Behaving Loop	3x3 boxes	Polarity Line	Kropki Dots
Magical Loop	Guiding cells	Modular Line	Magic Squares
Foggy Loop	Guiding cells	Parity Line	Fog of War, Killer Cages
10-Suȵ Loop	Moon-or-Sun	10-Line	Killer Cages
Counting Loop	Galaxies	Counting Line	Killer Cages, Kropki Dots, Quadruple Clues
Shining Loop	Moon-or-Sun	Parity Line	Killer Cages
Interfering Loops	Slitherlink + Masyu	Entropic Line + Parity Line	Killer Cages
Slithering Loop	Slitherlink	Entropic Line	Killer Cages, Little Killer
BigBang Loop	Galaxies	Parity Line	Row/Column Indexer, Kropki Dots
Summing Loop	Star Battle	Region Sum Line	Killer Cages, Skyscraper, Kropki Dots
Whispering Loop	Star Battle	German Whispers	Sandwich Sum