Logic Masters Deutschland e.V.

Normal Sudoku rules: pace the digits 1-9 once each in every row, column and 3x3 box.
Anti-Zebra: Two cells a zebra's move (2,3) apart cannot contain the same digit.
German Whispers: adjacent digits on a green line differ by at least 5.
Dutch Whispers: adjacent digits on a green line differ by at least 4.
Killer cages: digits in a cage sum to the total given in the corner.
Little killers: the digits on the indicated diagonals sum to the given totals.
Even: the digits in grey squares are even.

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N.B. "Zebra" is the name given in fairy chess problems to the (2,3)‑counterpart to the knight, as can be seen in the bonus chess problem with both knights replaced by Zebras. (e.g. white Zebra could play from b1 to d4).

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