Continuing the popular Overworked & Underpuzzled series, Serene Sudoku contains almost 200 of the ever-popular Sudoku puzzles to help focus your frazzled mind. There are nearly 200 puzzles, all of which are perfect for anyone who needs something to focus on during a brief break in their busy day. With multiple levels of difficulty provided, this is the perfect puzzle book for anyone who works too hard and loves the serene logic of a Sudoku.