This is a 9x9 map of the ocean - there are ocean cells and island cells. Normal sudoku rules apply. Digits in cages must sum to the small clue in the top left corner of the cage. Digits cannot repeat within a cage with nine or fewer cells. Cells separated by an X must contain digits summing to 10. Not all Xs are given. HOWEVER, 18 cells - two in each box, row and column -are 'island' cells - these do not count toward the cage totals. Only 'ocean' cells count towards cage totals. There can be as many island cells as needed in any cage.