Normal sudoku rules apply. The grid is partially covered in fog. Placing correct digits will clear the fog from surrounding cells. Digits on a black dot are in a 1:2 ratio. Split-Pea Lines: The sum of the digits on a line strictly between two circles is equal to a concatenation of the two values in the circles, in some order. For instance, 4-347-1 could be a valid split pea line, as 3 + 4 + 7 = 14, which is 1 concatenated with 4. Digits may repeat on a line if allowed by the other rules. Lines do not cross, branch or share cells with other lines, but they may share circles.