Logic Masters Deutschland e.V.

Rules
Normal sudoku rules apply.
The sum of the digits along an arrow is equal to the digit in the connected circle. In the finished grid, each 2x2 square of cells has to contain at least one low digit (1/2/3), one middle digit (4/5/6), and one high digit (7/8/9) [Global entropy].
Cells that appear in the same relative position in their 3x3 box must not contain the same number [Disjoint groups].

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