Normal sudoku rules apply. Finkz and Phinx must both reach the cupcakes by finding a path through the maze. The paths must not visit any cell more than once, cross themselves or each other, or pass through any thick maze walls. The paths may not share cells except where they meet at the cupcake cell. As well as moving orthogonally, Finkz and Phinx may move diagonally if there's a 2x2 space in which to do so, but may never pass diagonally through a round wall-spot on the corner of a cell. If two digits are joined by a blackcurrant then one is double the other. If two digits are joined by a redcurrant then one is even and the other is odd. If two digits are joined by a grape then they have a difference of at least 5. In this experiment, Finkz and Phinx both visit the same number of cells. Before reaching the cupcake, the Nth digit visited by Finkz and the Nth digit visited by Phinx always have the same difference (to be deduced.) This difference equals the digit on the cupcake cell. Eg: if the 3rd digit visited by Finkz is 5 and the 3rd digit visited by Phinx is 9, the cupcake cell would contain a 4.