Normal sudoku rules apply, i.e. put digits 1-9 in the grid so no digit is repeated in any row, column and 3x3 box.
Digits along arrows sum to the digit in the connected circle.
Digits on palindromes are read the same forwards and backwards. Different colours of palindromes do not apply any additional constraints.
Digits separated by X sum to 10. Digits separated by V sum to 5. Not all possible X's and V's are necessarily given.
Digit in a grey square is even.
Digit in a grey circle is odd.
Lösungscode: Column 3, Row 3