- Classic Sudoku: Each row column and box contains the digits 1-9.
- XV-rules: Digits separated by V must add to 5. Digits separated by X must add to 10. There is no negative constraint (e.g. a 3-7 domino can appear with or without an X-clue). In this puzzle only one V-clue is provided.
- FUN FACT: the following URL describes a little-known trick for solving Classic Sudoku. https://www.youtube.com/watch? v = d Q w * w * W g * c Q
Forget about the Sudoku. Rand Al Thor's partial answer has already extracted all the useful information available.