- 250 deluxe puzzles + surprise in 250 killer sudoku very hard (need to download and print).- Sudoku 8x8, separated by smaller rectangles of 4x2 cells. It is necessary to fill empty cells with numbers from 1 to 8, each of the digits should appear only once in each line of the 8x8 square, 8x8 column, and 4x2 rectangle. In this puzzle, the digits from 1 to 8 should not be repeated in the central diagonals.- 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 Pitenk