Logic Masters Deutschland e.V.

This puzzle was created for a setting impersonation event hosted by Isamook. My target was Donatello_86, and after a very enjoyable browse of his catalog, I thought it would be fun to combine the ideas behind these two puzzles. Big thanks to Donatello for the inspiration, Isamook for the prompt, Ratfinkz for all her work organizing the event and Calvinball for testing! The event was a blast! On to the rules in my best Donatello impression:

Rules:

1. Place the digits one through nine in every row column and 3x3 box.

2. Shade in two colours, so that both colours form two orthogonally connected regions. One of the colours will represent negative values and the other positive values. No 2x2 region is fully one colour. Place a colour in the cell, but only once it is determined to be either a positive or negative value. No cell should be shaded prior to its sign being definitively known.

3. Cells separated by a white dot contain consecutive values.

4. Digits on an arrow sum to the value in the attached circle.

5. Every visible arrow also has a corresponding invisible arrow that will be revealed as the puzzle is shaded. The paired invisible arrow will be the same length as its visible pair. If the visible arrow sums to D, the corresponding invisible arrow will sum to negative D. Position one of an arrow starts at the circle and the position increases along the line. If the cell in position X of the visible arrow (starting from the circle) is positive, then the cell in position X on the corresponding invisible arrow will be negative, and vice versa. Arrows do not split or share cells.

6. An arrow outside the grid indicates the sign of the sum of the digits along the diagonal it points at. A + by the arrow indicates the sum will be positive, and a - indicates it will be negative.

Hope you enjoy, and click the puzzle to play!