Akin
- Kropki dots
- Region sum lines
The brief
- Normal sudoku rules apply, i.e. each row, column, and 3x3 region has to contain the digits from 1 to 9 once each.
- Region Sum Lines: Box borders divide the blue lines into segments with the same sum. (Different lines may have different sums.)
- Kropki: Digits joined by a black dot are in a 1:2 ratio. Digits joined by a white dot are consecutive. (Not all black and white dots are necessarily given.)