Logic Masters Deutschland e.V.

I've wanted to set this puzzle since before I published my very first Sudoku on LMD. However, I knew I needed to gain some experience as a setter before attempting such a complex puzzle, so I set the idea aside and focused on designing puzzles with some simpler variants. A few weeks ago, I finally felt ready to tackle this challenge and spent several hours playing around with doublers and the complicated interactions they have with German Whispers. After much wrestling with the puzzle trying to implement the ideas I wanted the puzzle to contain and eliminating several less interesting variations, I eventually was able to craft this beautiful layout - which is quite sparse for a digit modifier puzzle! The break-in to this puzzle is quite challenging, but a list of logical deductions exists that clearly leads to the single solution that satisfies all of the constraints. As this puzzle is considerably harder than my standard puzzles, I have included a list of hints at the bottom of the page in case anyone is struggling with the break-in :)

I decided on the name of this puzzle very early on, referencing a funny moment from the Doctor Who series (screenshots from the scene included below for any non-Doctor Who fans!). However, I didn't realize that I could visually represent the face of Matt Smith's Doctor until about halfway through the design phase (Note the bowtie whisper!). I reshaped everything I had so far and I am still completely stunned by how cleanly this design was able to work out! Hopefully everyone can see how the long whisper in boxes 1, 2, and 3 represents hair, the box 4 whisper an ear, the box 5 whisper a nose, and the row 8 and 9 whisper the iconic bowtie from the Eleventh Doctor. Now the Doctor's face needs solving, so please enjoy my first digit-modifier puzzle, Confusing the Polarity!

Normal Sudoku rules apply.

German Whispers: The values of digits in adjacent cells on a green line differ by at least 5.

Doublers: There are 9 doublers in the grid - one in each row, column, and box. For the purposes of German Whisper lines, digits on doublers count as double their value. No two doublers contain the same digit.

Solve on F-Puzzles (Turn off highlight conflicts - f-puzzles doesn't recognize the effects of doublers!)

Solve on CtC App

Hints - Each hint builds upon the last. (highlight to reveal):

1. Placing the first digit in this puzzle requires consideration of 3/4 whisper lines.

2. 5 must be placed somewhere in both boxes 1 and 3. Consider the different ways this can be achieved and note that boxes 1 and 3 cannot both double the same digit.

3. Do you know anything about the polarity of the cells in box 2 that are on the whisper line?

4. How can the whisper in box 5 possibly be true? What about the whisper in rows 8 and 9? How many times in the entire grid can this trick be done?

Good luck!