Big Book of Jigsaw Sudoku : 400 Jigsaw Sudoku Puzzles

Printed on high-quality paper that will easily withstand the constant erasing and re-writing that a Sudoku puzzle requires, this book contains 400 graded Jigsaw Sudoku puzzles. The 400 puzzles are broken down as... 100 easy puzzles. Perfect if you've never played Jigsaw Sudoku before! 100 medium puzzles. A little more challenge. 100 hard puzzles. 100 tough puzzles. Perfect for those who are experienced Jigsaw Sudoku puzzlers looking for extra challenge. Every puzzle has a unique solution and can be solved by logic alone - no guessing required. Full answers are given in the book. Jigsaw Sudoku is very similar to standard Sudoku, but instead of all the regions being 3×3 squares, they are instead irregular 'jigsaw' shapes.