Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.
Rules – Follow regular Sudoku rules. Additionally, if the difference between two cells is 1 then there is a white dot. If digit in a cell is the half from a neighboring cell then there is a black dot. The dot between two cells with 1 and 2 can have any of these two colors. All possible dots are given.