Logic Masters Deutschland e.V.

There has been over the last few weeks (and even days*) quite a bit of activity around the fringe variant that is the Doppelganger ruleset, including what are surely some of the hardest ones ever created with it: And so to help keep this momentum going despite a busy summer, here is a pure German Whisper 8x8 from the Discord Archive. The difficulty will be anywhere between 2 and 4 depending on your familiarity or grasp of the mechanics of the ruleset, and a practice 4x4 if also offered below the main puzzle.




SOLVING LINKS (all tracking cells required for the solution check)

Solve on Sudokupad
Solve on Penpa

RULES

DOPPELGANGER
– Every row, column, and box contains the digit 0 always, as well as seven out of the eight digits from 1 to 8 (ie, it's missing a digit that is not 0)
– No two rows, no two columns, and no two boxes may be missing the same digit
– For each 0 in the grid, the digits missing in its row, its column and its box must be three different digits (yet zeros have a null value – ie zero)

GERMAN WHISPERS
– Adjacent digits along green lines must have a difference of at least 5