Logic Masters Deutschland e.V.

Old MacSudoku had a farm, E-I-E-I-O
And on that farm... Normal sudoku rules apply.

Old MacSudoku raises a variety of special digits. They normally graze in their respective pens (boxes 2, 4, 6 and 8), however some have escaped into the central field, box 5!

For each of the special digit types, mark 9 cells containing the digits 1-9 for that type. Those cells must either be in the pen that holds that type or in the central field, box 5. (eg if box 2 was the pen for Whisper digits, all 9 Whisper digits would appear in boxes 2 and 5)
The type of each pen is to be determined by the solver.

Grey cells indicate digits that have escaped from their pen, and do not contain special digits.

Any two orthogonally adjacent digits of the SAME type follow special rules, the rules for each type are as follows:
Whisper - the digits must differ by at least 5
Shout - the digits may not differ by more than 4
Prime Parity - both digits are either prime (2,3,5,7) or non-prime (1,4,6,8,9)
XV - the digits sum to either 5 or 10

eg Whisper digit 7 cannot be orthogonally adjacent to Whisper digit 4 (as it differs by only 3), but it can be adjacent to a non-special digit 4, or to Prime Parity digit 4 (as they are of different types).

The given lines treat adjacent digits along them as though they were orthogonally adjacent digits of a given type:
Green - Whisper
Pink - Shout
Blue - Prime Parity

eg if r6c5 is prime, r5c6 must also be prime, but they are not necessarily Prime Parity digits themselves

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