Normal sudoku rules apply. Cells separated by a (chess) knight’s move cannot contain the same digit. Any three consecutive cells along a green (modular) line must contain one digit of each residue class modulo 3: {147}, {258} and {369}. Digits joined by a black dot are in 1:2 ratio, digits joined by a white dot are consecutive, and digits joined by a green dot are both in the same residue class modulo 3.