Logic Masters Deutschland e.V.

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This puzzle is part of my snackdoku series. Snackdokus are sudoku puzzles that are generally smaller (4x4 grid) and simpler to solve. This one, however, is a bit tougher compared to my previous snackdokus, expecting some contradiction-y logic.

Rules:

• Normal sudoku rules apply (4x4): Place the digits 1-4 in each row, column, and 2x2 box without repetition.
• Slow Thermometers: Digits on thermometers either increase or stay the same as they progress from the bulb to the tip. The thermometers are colored to help specify the direction each one goes. To be clear, each thermometer's path is shaped like a U.

Solve on SudokuPad here!

To increase accessibility to my puzzles, I include hints in my puzzle posts (see below). I also post solution videos on my Patreon and YouTube channel. Puzzles released prior to February 2026, as well as my snackdoku and variant sudoku 101 series will continue to get public solution videos on YouTube, while others will be Patreon-exclusive.

Hint 1: The only bit of advice that's particularly helpful for this puzzle is to be generous with your pencilmarking of each slow thermometer here. Start by taking note of how the low digits must minimally progress, and then how the high digits must maximally progress, and go from there. Always be sure to update the pencilmarks, if needed, whenever you place any digits onto one of the thermometers.