Sudokus are the ever-popular number placements puzzles that give your brain a workout. Spanning across a number of difficulties, this bumper collection of more than 900 puzzles is sure to keep you entertained for hours. - EXERCISE YOUR BRAIN: Give your mind a great workout as you pit your wits against these number-placement teasers. - REDUCE STRESS: Feel your stress melt away as you focus on these satisfying puzzles. - OVER 900 PUZZLES AND SOLUTIONS: This bumper book of puzzles will provide hours of entertainment.