Some people consider Sudoku Samurai puzzles too big; some other people prefer even bigger Sudoku variant puzzles. If you belong to the second category, this book is for you It's full of overlapping 13 grid Sudoku puzzles (Gattai-13) laid out in a quadruple Samurai Sudoku format. Essentially, there are 13 Sudoku sub-puzzles which overlap the same way as in Samurai Sudoku. So it is like having 4 Samurai Sudokus on top of each other This books comes from Djape who has been supplying Sudoku Samurai puzzles for The Washington Post since 2005. Are you up for this challenge?