Double Samurai Sudoku Harakiri: 81 Overlapping Sudoku Puzzles, 8 Grids in 1

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 8-grid Sudoku puzzles (Gattai-8) laid out in a double Samurai Sudoku format, also known as SUDOKU HARAKIRI.
Essentially, there are 8 sudoku sub-puzzles which overlap the same way as in Samurai Sudoku.
Therefore, each puzzles provides twice the challenge of an ordinary Samurai Sudoku!
Are you up for this challenge?