Logic Masters Deutschland e.V.

Continuing the mark of my 1-year setting anniversary (for the previous puzzle - Harmony - check out this link), I decided to do quite a big project: trying myself at setting a big puzzle.

Specifically, it's a big puzzle containing six different 6x6 sudoku grids, which are linked together by circles. This one is hugely inspired by Genomico's fantastic Linked Sudokus series and Sam Cappleman-Lynes's lovely 6x6x6 puzzle (also thanks to both constructors for the great fun from these treats!). It's definitely the longest work that I've analyzed on so far, where so many wrong things can happen in one such puzzle, but the final result was so satisfying that I couldn't even be thankful enough for it for happening. I hope you enjoy the puzzle! :)

Rules:

- Normal 6x6 Sudoku rules apply for all the 6x6 grids: every row, column and bold 3x2 (or 2x3) region contain digits from 1 to 6 each once.

- Each 6x6 grid has a different variant that applies on their own grid, listed as below:
+ German Whisper: Adjacent cells along a blue line must contain digits that have difference of at least 3.
+ Killer (cages): Digits within a cage can't repeat, and they sum to the small number written in the top left of that cage.
+ Consecutive Line: adjacent cells along the red line must contain consecutive digits.
+ Mathrax: Each circle contains a number and an arithmetic operator, where the number is the result when you apply that operation to both pairs of diagonally opposite cells.
+ Arrows: Digits along an arrow must sum to the digit in the circle cell attached to that arrow.
+ Thermometer: Digits must strictly increase from the bulb to the end.

* A digit in the circle outside the sudoku grids (between two adjacent sudoku grids) shows the number that is the difference of THE SUMS OF TWO CELLS from both sides of that circle.
For example, a circle that has [2,5] from one side and [3,1] from other side will have 3 in it, since (2+5) - (3+1) = 3.
** In a series of six consecutive circles, NO TWO OF THEM WILL CONTAIN THE SAME NUMBER.
For example, if one circle contains a 3, no other circle in the series of six circles containing that circle will contain a 3.

Puzzle: Penpa+ link

Good luck and have fun solving!