Then this book is the perfect antidote to sharpen your thinking, improve attention and boost your memory! In the Sudoku Ominibus, you get: More than 100 sudoku puzzles of varying difficultyevels. Fourevels of difficulty (easy, medium, hard and nasty). Solutions at the end of each part. Sudoku grids which arearge, easy to read and fill out. So get those grey cells working.