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 one or more different digits. The full sequence must appear at least twice along the line and must always repeat in its entirety. Different lines may contain different sequences.

**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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