Cells containing numbers are on islands and stay white. White islands must have a number on them somewhere.
Numbers tell the number of continuous white cells on an island. Each area of white cells contains only one number in it and they are separated by green water cells. White islands can touch other islands diagonally
Green water cells are linked to be a continuous body of water connected vertically and horizontally.
Green water cells cannot be linked to be 2x2 square.