“ChoGekikara (Really really hard) Sudoku 17”
“Cho-Gekikara (Really, really hard) Sudoku” contains 91 sudoku puzzles.

“Nankan(Hard)Sudoku 17”
“Nankan (Hard) Sudoku” contains 105 sudoku puzzles.

“Otegaru Slitherlink”
This book contains 60 Slitherlink puzzles ranging from easy to medium.
All the included puzzles are reprints from “SLITHERLINK (Large letters — clear & easy)”.

“Have a Ball with Pencil Puzzles — Crossword Puzzle 1”
This book contains over 50 crossword puzzles from easy to hard.

“Just Right! Sudoku (a bit hard) 5”
This book contains 105 Sudoku puzzles, most of which are of medium difficulty.

“Have a Ball with Pencil Puzzles—Kakuro for expert5”
This book contains over 90 Kakuro puzzles for experts.

“Have a Ball with Pencil Puzzles—Slitherlink for expert5”
This book contains over 90 Slitherlink puzzles for experts.

“A Puzzle Book with Lots of Kanji Readings”
This book has more than 50 puzzles, mainly of four different types that require knowing kanji readings.

“Nikoli Puzzle Book Reprint Edition Kakuro 3”
The puzzles in this volume are all the puzzles of “Pencil Puzzle Book Kakuro Vol.12”. This volume contains 92 puzzles.

“Gekikara (Super Hard) Sudoku Best Selection 1”
This book contains more than 100 Sudoku puzzles, which are of the hard difficulty level.
These puzzles were published in the NIKOLI “Gekikara (Super Hard) Sudoku” series and have been re-edited with the excellent results published here.