Logic Masters Deutschland e.V.

Inspired by Arrowdynamics, hence the title (can you spot the connection?). The rules are slightly different. Enjoy!

Rules:

Normal sudoku rules apply.

Arrows that cover two cells are Double-Digit Summation Arrows. The digits in the two cells covered by such an arrow form a two-digit number when read in the arrow's direction, which is equal to the sum of all cells further along in that arrows direction (in the same row/column/diagonal).

Digits may not repeat in a cage.

Digits separated by an 'X' sum to 10. Not all 'X' are given.

Optional rule: Let me know what you think!