Logic Masters Deutschland e.V.

SudokuPad link (via tinyURL)

Normal Sudoku rules apply. Place the digits 1 through 6 in each empty cell. Digits must not repeat within the same row, column, or box.
Renban: digits along a pink line form an unordered consecutive set of numbers.
Doublers: one digit in each row, column, and region are 'doubled' for the purposes of other clues. A length 4 renban, for example, could have the digits 2235 if one of the 2s was doubled. Each digit is doubled exactly once.