The Pencil Puzzles 20xx series are the renewal versions of our best sellers "Penpa 20xx" series. The book contains about 260 number puzzles, includes English explanation. The names and numbers of puzzles included are below. Double Choco 24 Numberlink 27 Nurikabe 27 Masyu 27 Fillomino 23 Heyawake 28 Yajilin 28 Slitherlink 32 Kakuro 20 Choco Banana 21