Good fitness for the brain. 100 puzzles Sudoku Calcudoku 9x9 - Hard Levels. 100 puzzles Kakuro - 9x9 + 10x10 + 11x11 and 12x12 puzzles. 100 puzzles Jigsaw Killer Sudoku - Hard levels. 100 puzzles Tridoku Sudoku 9x9 - 25 Hard levels. - unique puzzles. Calcudoku - this is a mathematical and logical puzzle. It is necessary to fill the grid with numbers so that in each line and in each column they are not repeated. The number in the corner of each selected block is the result of an arithmetic operation on the digits in this block. The numbers inside the block can be repeated. The puzzle can be called Square Wisdom, Kendoku. Kakuro is a logical numerical puzzle, the mathematical equivalent of a crossword puzzle. In the cells it is necessary to place the numbers from 1 to 9, there are inactive cells (marked in black). In cells with given numerical values, the upper right value indicates the sum of the digits in the row, and the value from the lower left position is equal to the sum of the digits of the column below the cell. For example, the number 6 can be represented as a sum of 2 and 4 or 1 and 5; the same numbers (3 and 3) are not allowed. Jigsaw killer sudoku - This Sudoku leads step by step to the top of the skill. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each row and column of the 9x9 square. The puzzle contains areas in an arbitrary form. The sum of all the numbers in the cage must correspond to the number printed in the corner. They can be called figurative or geometric, they also have names (Killer Jigsaw Sudoku, Killer Geometry Sudoku, Killer Irregular Sudoku, Killer Kikagaku Nanpure). Tridoku. The puzzle consists of nine large triangles. Each of them contains nine small triangles. Figures from 1 to 9 should be placed in the cells of each large triangle. The field contains additional lines, the cells of which must also contain non-repeating numbers. Two adjoining triangular cells should not contain the same numbers (even if the cells touch each other with only one point). + 250 sudokus difficult level that can be downloaded and printed. + 250 maze puzzles that can be downloaded and printed. - only 1 verified solution. - all answers are at the end of the book. - exclusive puzzles. - a link to the surprise is at the end of the book. An excellent book for free time and mind exploration. I hope you enjoy the book. Best regards, Basford Holmes