Cuatro Cruces
- Killer cages
- Diagonals
- Arrows
- Whisper lines
The brief
Standard sudoku rules apply: each row, column, and 3x3 box contains all the digits from 1 to 9.
Each marked diagonal contains no repeated digits.
Digits on arrows sum to the number in the attached circle or pill. Two digit sums are read in the direction of the arrow.
The green line is a German Whispers line: adjacent digits along the line must differ by at least 5.
Digits cannot repeat within a cage. The digits in each cage sum to more than 40. The sums are not necessarily distinct.