Logic Masters Deutschland e.V.

Normal sudoku rules apply.

Skyscrapers: Clues outside of the grid indicate how many digits are larger than all other digits that come before them, reading from the direction of the clue.

Zippers: On a purple line, pairs of digits equidistant from the center sum to the central digit of their line.

The grey lines are palindromes in which digits read the same forwards and backwards.

Digits in circles must be the exact and only digits assigned to its surrounding cells.

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