25 books
Revenge of Killer Sudoku 5
Killer Sudoku and other puzzle variants
Jigsaw Sudoku Compendium
Revenge of Killer Sudoku 4
The Way of Samurai 120 Samurai All new Sudoku puzzles
Triangular Sudoku
Samurai Sudoku and other puzzle variants
Outside Sudoku and its variants
Zero Killer Sudoku
Jigsaw Sudoku vol 2
Killer Sudoku Compendium
Hitori
Sudoku Straights
Revenge of Killer Sudoku
Square Wisdom
The Way Of Samurai 3
Picross, Hanjie, Griddlers, Nonograms
Djape Does Sudoku
Diagonal Sudoku
Jigsaw Sudoku
Hidoku
Revenge Of Killer Sudoku 2
Killer Samurai Sudoku
The Way Of Samurai