Logic Masters Deutschland e.V.

Normal sudoku rules apply.
Exactly one cell in each row, column, and box is a "doubler", and doubler cells contain a complete set of the digits 1-9. The value of a doubler cell is equal to its digit multiplied by two. (Other cells have a value equal to their digit.)
Skyscraper clues: clues outside the grid indicate the number of values visible in that direction, where higher values block the view of values that are equal or lower.
Cages: the sum of the values inside each cage is equal to the small number in the top left corner.
Values in cells with a shaded square are even.
Values in cells with a shaded circle are odd.

SudokuPad

This puzzle was originally released (and solved by Scojo) during the 48-hour Sudoku Twitch Train on May 2-3. The purpose of the Train was to raise money for Sven Neumann and SudokuPad—which is still a good cause, so please support Sven if you can!

For more of my puzzles, check out Artisanal Sudoku, the weekly newsletter, or Artisanal Sudoku, the recently-released book. Thanks!