Logic Masters Deutschland e.V.

Normal sudoku rules apply.

Green lines are German Whisper lines wherein digits must differ by at least 5.

The orange line is a Dutch Whisper line wherein digits must differ by at least 4.

The blue line is a Region Sum line wherein 3x3 box borders divide it into segments with the same sum. There is only 1 region sum line in this grid that spans from r1c3 to r9c7.

The grey line is a palindrome in which digits read the same forwards and backwards. The palindrome in this grid is covering a portion of the german whisper in box 1 that does in fact extend to r3c3 to complete the letter 'C.'

Red lines contain digits of the same parity. There are 2 such lines.

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