Normal sudoku rules apply. The digits in each 2x2-square that crosses at least one box border sum to a multiple of eight - except for the square marked in grey. The digits along an arrow sum to the digit in that arrow’s circle.
Normal sudoku rules apply. The digits in each 2x2-square that crosses at least one box border sum to a multiple of eight - except for the square marked in grey. The digits along an arrow sum to the digit in that arrow’s circle.