Logic Masters Deutschland e.V.

Chaos Construction: Divide the grid into nine orthogonally connected nine-cell regions. Place the digits 1-9 into each row, column, and region.

Echo Lines: Indigo lines are filled with a repeating sequence of different digits. The sequence must appear at least twice along the line and must always appear in its entirety.

**No digit may appear on more than one echo line.**

Echo Chambers: For each echo line, each iteration of its sequence must be contained entirely within one region.

Arrows: A digit on an arrow indicates the number of region borders in the direction of the arrow. A cell with multiple arrows counts the number of borders in each direction separately. The outer edge of the grid is not considered a region border.

**All possible arrows are given.**

Circles: A digit in a circle indicates the number of region borders seen from that cell in all orthogonal directions combined.

Kropki Dots: Digits separated by a black dot must have a ratio of 2:1 (i.e. one must be double the other).

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