Book excerpt: 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?