Normal sudoku rules apply. In cages, digits must sum to the small clue in the top left corner of the cage. Digits along an arrow must sum to the digit in that arrow's circle. Navigate the maze by carefully plotting an orthogonally connected path from the green cell to the red cell. The path must include every cell containing an arrow, first entering the bulb and then travelling directly along the arrow. Every cell in the grid is associated with a cardinal direction (NESW), given by its digit modulo 4. The path must exit every cell it enters according to these directions. Which direction corresponds to which digits is to be discovered.