Logic Masters Deutschland e.V.

Rules:

• The grid contains nine non-overlapping 3x3 boxes which you must locate. Each box contains the digits from 1 to 9 with no repeats. Each row and column of the entire 11x11 grid also has no repeated digits.
• Each arrow indicates a diagonal of the grid which contains a non-empty cell. The first digit seen by each arrow is the number of non-empty cells in the diagonal. Additionally, in each diagonal indicated by a black arrow, digits either stay the same or increase when traversing from the lower left to the upper right (rather than the direction suggested by the arrow). However, the red arrow does not constrain its diagonal in an analogous way.

Here's an example grid to demonstrate the ruleset: