Logic Masters Deutschland e.V.

(This is one of a series of puzzles using the entropic/modular constraint. If you like it, give the others a try! Deadlines, Hotlines, Triplines, Bowlines)

Place the digits 1 to 9 once into each row, column, and 3x3 box. Digits in a cage must add up to the given sum.

Each row and each column is either an entropic line or a modular line. On an entropic line, each set of three consecutive digits must contain a low (123), middle (456), and high (789) digit. On a modular line, each set of three consecutive digits must contain one equivalent to 1 mod 3 (147), one equivalent to 2 mod 3 (258), and one divisible by 3 (369).

(Lines of the same type that cross are considered separate lines. E.g. if row 1 and column 1 were both entropic, R1C2 and R2C1 could both be low since they're on separate lines.)

Online solver: SudokuPad