Logic Masters Deutschland e.V.

Thanks to the rule created by Phistomefel, I used it to come up with another puzzle.

I set the difficulty to 4 stars, but if you come back after finishing Phistomefel's puzzle’, it'll be 1 star.


Rules
Normal Sudoku rules apply.
An inner square is a 2x2 square that crosses no box border. For all inner squares, the two diagonals sum to the same number. The diagonals of different inner squares may sum to different numbers.
The number in the center cell of each box can't be bigger than the box's No. (For example: in the 5th box, R5C5's number may be 12345), and it also has to be unique on both diagonals that cross it.
Finally, Find the longest thermometer in the grid without any turns.


PLAY IN SUDOKUPAD