Title: Toral Rorschach
Another sum puzzle, and another toral puzzle (the fourth, after Prorus, Circuitry, and Fundamentals). The properties of a toral board are in the last rule below.
The official rules:
- The digits 1 through 9 appear in each row and each column exactly once.
- Digits in each shaded region must add to the indicated sum.
- Squares with multiple colors contain a number that’s used in the sum for adjacent regions of each of those colors.
- Remember: numbers can repeat within a shaded region if that doesn't violate the first rule.
- The board is a “toral board,” that is, cells at the end of one row are considered adjacent to those at the beginning of the same row; cells at the end of one column are considered adjacent to those at the beginning of the same column, and all corner cells are considered adjacent.