This popular, even more challenging variant of sudoku is for true puzzle warriors Each one consists of FIVE sudoku grids arranged in an X-shaped array, with overlapping corners. No grid can be solved on its own; to complete the entire puzzle, players have to work on several grids at once, making their way to overlapping areas and constantly searching for new clues.While regular sudoku-solving techniques provide the starting point, the game s more complicated than that. Because the overlapping areas belong to two different grids, they must comply with the rules of both simultaneously. That changes the puzzle s underlying logic and makes these sudokus more fun for the serious fan. An introduction, with a sample puzzle, shows all the strategies.