Hard Sudoku X Puzzle Book for Adults: 250 Hard Sudoku For Advanced Players - Paperback

250 excellent puzzle 9x9 at the level of Hard. All riddles have only 1 solution. 2 puzzles per page.The font size is correct, you will not have to strain your eyes when solving puzzles.For Advanced Players .High quality paper and print (all puzzles read well, easy to write with pen and pencil without worry of bleed-through).Sudoku X is based on the original Sudoku grid, with the same rules and numbers-1 to 9(no number may appear twice in any row or column and rectangles of 3x3).Sudoku X (Diagonal Sudoku) puzzles both diagonals must contain all digits from 1 to 9 precisely once