- 250 deluxe puzzles + surprise in 250 killer sudoku very hard (need to download and print).- Sudoku 9x9. The entire playing field consists of 81 cells. It is required to fill empty cells with numbers from 1 to 9. Numbers from 1 to 9 are not repeated in the columns and rows of the square 9 x 9. The puzzle contains areas in an arbitrary form. They can be called figurative or geometric, they also have names ("Jigsaw Sudoku", "Geometry Sudoku", "Irregular Sudoku", "Kikagaku Nanpure").- levels continue to please. 50 Easy + 50 Medium + 50 Hard + 100 Very hard- all riddles have only one verified solution- 2 puzzles on 1 page, very practical and convenient- a lot of free space for the progress of your thoughts- good mind support in the excellent form- large font- develops memory, logical thinking, helps to focus- creative possibilities are expandingIdeal gift for all fans of puzzles. An excellent book for free time and learning of the mind. I hope you enjoy the book. I would be very grateful if you write a review.Best regards,Andrii Pitenko