Logic Masters Deutschland e.V.

Normal sudoku rules apply.

Minimal between lines
Digits on a line must be between the digits in the connected circles. The difference between the circled digits must be as small as allowed by normal sudoku rules. A difference of zero is possible. Examples are provided below.

F-Puzzles link: https://f-puzzles.com/?id=yyulf2al

Minimal between line examples

The circle in R1C2 connected with a straight line to the circle in R5C6 must have a difference of 2 because it is possible (and necessary) to repeat the same digit in all 3 spots along the line. The circles in R6C3 and R7C4 have a difference of zero since there are no digits on the line between them.