Logic Masters Deutschland e.V.

The constraint used in this puzzle isn't completely unique, but it is quite a rare one. Increasing Lines simply have digits in increasing order, but the catch is you don't know which direction the digits increase. It is completely valid to think of these lines as ambiguous direction thermos with the bulbs missing (but you are guaranteed that the bulb is at one end or the other, not somewhere in the middle). I easily could have called this constraint some variation of ambiguous thermos, but there are plenty of name variations on thermos as is, and I rather liked the name "Increasing Lines" inspired by Richard's SVS 073, which uses the exact same constraint but quite a different approach to the puzzle. I intentionally chose to use thicker lines with a very greyish color (#AAAAFFCC) for Increasing Lines specifically to make them visually resemble thermos. Increasing Lines are quite a tricky constraint to work with both as a setter and a solver, but I tried to not go overboard on the difficulty with this one. Once you get a foothold in this puzzle, it shouldn't be too difficult to finish even if you've never worked with this constraint before. I hope you enjoy my latest puzzle, Inner Harmony! Good Luck :)

Update: This puzzle was featured on Cracking the Cryptic! Watch Mark's solve of the puzzle here!

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Normal Sudoku rules apply.

Increasing Lines: Digits along a lavender line strictly increase in one direction or the other.

Kropki Pairs: Digits separated by the white dot are consecutive. Digits separated by the black dot are in a 2:1 ratio.

Solve on F-Puzzles

Solve on CtC App

If anyone is interested, I recreated Richard's SVS 073 in SudokuPad using my aesthetics here.

By the way, can anyone figure out the meaning behind the title of my puzzle? :)