Sudoku Variants Collection Volume 2: 3 Variant Types, 270 Easy to Hard Puzzles : Killer Sudoku, Even-Odd Sudoku & Chain Sudoku

This book comprises three sudoku variants: killer sudoku, even-odd sudoku and chain sudoku. And each variant type includes 90 puzzles: 30 easy level, 30 medium level and 30 hard level. Rules of sudoku variants are mostly the same as classic sudoku, and we have instructions about each puzzle type so that you know the difference before start playing the games. This is a great gift for anyone who loves sudoku puzzles and want to try different variant types.