This second book in the series is for savvy sudoku solvers who are looking for puzzles that are harder than hard. Features:· 200 fearsome puzzles· Edited by legendary New York Times crossword editor Will Shortz· Portable and affordable packageAlso in the series: -Will Shortz Presents Difficult Sudoku -Will Shortz Presents Dangerous Sudoku | Will Shortz Presents Daring Sudoku, Paperback | Indigo Chapters