Hard Puzzles Book - Sudoku X, Anti Diagonal Sudoku, Killer Sudoku, Consecutive Sudoku - 200 Hard Puzzles vol.7

- (Sudoku X) Each puzzle consists of a 9x9 grid containing given clues in various places. The object is to fill all empty squares so that the numbers 1 to 9 appear exactly once in each row, column, diagonal and 3x3 box.-(Anti Diagonal Sudoku) Place a digit from 1 to 9 into each of the empty cells so that each digit appears exactly once in each row, column and 3x3 outlined box. Additionally every main/marked diagonal contains only 3 different numbers-Killer Sudoku is a mix of Sudoku and Kakuro. Your goal is the same as in regular sudoku: fill every row, column and 3x3 region with the numbers 1-9 once. The difference is how you arrive at those numbers. The objective is to fill the grid with numbers from 1 to 9 in a way that the following conditions are met: Each row, column, and nonet contains each number exactly once. The sum of all numbers in a cage must match the small number printed in its corner. No number appears more than once in a cage. (This is the standard rule for killer sudokus, and implies that no cage can include more than 9 cells.)-A Consecutive Sudoku puzzle adds one extra constraint to the standard Sudoku grid - not only must you place 1 to 9 (or 1 to whatever the width of the puzzle is) in each row, column and bold-lined box, but also obey the white consecutive markers: White bars between squares indicate that the squares are consecutive - meaning that the numbers in these two squares have a numerical difference of '1'. For example: 1 and 2; or 4 and 5. If there is no white bar then the numbers are not consecutive.