510 books • 53 series
Master of Puzzles - Numbricks 200 Medium to Hard Puzzles 10x10 Vol. 13 (Numbricks, #13)
Master of Puzzles - Killer Sudoku 200 Medium Puzzles 10x10 Vol. 16 (Killer Sudoku, #16)
Master of Puzzles - Killer Sudoku 200 Easy to Master Puzzles 10x10 Vol. 19 (Killer Sudoku, #19)
Master of Puzzles - Numbricks 200 Easy to Medium Puzzles 10x10 Vol. 12 (Numbricks, #12)