Normal Sudoku rules apply. Digits connected by a white dot are consecutive. Digits connected by a black dot are in a ratio of 2:1 (ie one digit will be double the other). Not all dots are necessarily given. Coloured lines in the grid are “Renban” lines. Digits on a Renban line form a set of non-repeating, consecutive digits – these digits can appear in any order. All Renban lines in the grid move orthogonally between neighbouring cells, do not branch and do not overlap each other. Each line has a unique colour. The grid is covered with fog. Correctly placed digits will clear the fog around that cell.