Here's a real treat for all fans of the number-placement puzzle sudoku: a collection of more than 500 grids arranged by level of difficulty. Sudokus are fun and satisfying to solve, and give our brains a good workout too. This elegantly designed collection will satisfy even the most ardent enthusiast, and the beginner can enjoy the pleasure of working up through the levels as their solving skills improve. - MORE THAN 500 PUZZLES AND SOLUTIONS This bumper book of puzzles will provide many hours of entertainment. - EXERCISE YOUR BRAIN These number placement puzzles will be sure to give your brain a stimulating workout. - IMPROVE YOUR SKILL Enjoy the satisfaction of seeing your ability to solve the puzzles improve as you work through the five levels from beginner to expert.