Normal sudoku rules apply. All cells are either island or water. Each purple cell is an island cell. Each island must contain exactly one purple cell. Different islands may not touch orthogonally. The water cells are orthogonally connected and may not contain any 2×2 areas of water. Each island also contains a set of non-repeating digits that sums to the purple cell total if given. If no total is given, the sum is 6, 9 or 25. The number in the purple cell is the number of cells in the island. Totals are not necessarily in the top left most cell of an island. All islands are normal except one - Treasury Island, which has no given total. On this island, X's mark the spot - i.e. Treasury Island can be evenly divided into non-overlapping dominoes that each sum to 10; also, the purple cell's digit is inconsequential and digits may repeat.