Normal sudoku rules apply. The “goose path” from r9c2 to r1c8 is orthogonally connected, visits every cage and box and does not touch itself orthogonally or diagonally. Cages contain no repeated digits and show the total of the cells in the cage that are not on the goose path. Grey squares are not on the goose path, and show even digits which count the goose path cells in the adjacent (including diagonal) cells.