Normal sudoku rules apply. Some Japanese sums rules apply: There is a 6x6 grid in boxes 5/6/8/9. Blue cells in boxes 2/3/4/7 act as Japanese sum clues for this 6x6 grid, giving the sum of contiguous runs of blue-shaded cells within the grid. Two-digit clues are read top-to-bottom or left-to-right. There must be an unshaded cell between runs of the same color. A black dot separates digits with a 1 to 2 ratio. A white dot separates digits with a difference of 1 (or the given number when given). Not all dots are given. Fog rules apply. The fog will clear as you place digits correctly.