Normal sudoku rules apply. Clues outside the grid function as BOTH Sandwich and X-Sums Clues. In addition, Queen and King sudoku rules apply. 1. X-Sums: Numbers outside the grid indicate the sum of the first X digits in the corresponding direction. X is the first digit in the corresponding direction. 2. Sandwich: Numbers outside the grid indicate the sum of the digits between the 1 and the 9. 3. King: No digit can lie a "king's move" away from an equal digit (i.e. no digit can be adjacent to an equal digit, even diagonally). 4. Queen: You cannot repeat the number 9 within a "queen's move" (ie along the same diagonal).