Due to popular demand, having published numerous books with Killer Sudoku puzzles which contained puzzles of all difficulties, this time Djape has decided to publish a book only with the toughest and deadliest Killers.By no means is this a book for a novice Killer Sudoku solver. It is intended only for the most experienced and most persistent of those who are already masters at solving Sudokus with sums.It contains only puzzles of the 3 hardest levels of difficulty which Djape produces: BRAIN, IQ and INSANE, with addition of a few puzzles of an even more fiendish kind - Zero Killer Sudokus.40 BRAIN (5 diagonal)50 IQ!10 ZERO (including 8 ZERO INSANE)11 INSANE!For a total of 111 most difficult Killer Sudoku puzzlesSo... are you up for this challenge?