In Outside Sudoku, the clues are outside the grid instead of inside the grid. Each clue facing a row or a column must be put in the first three cells of the corresponding row or column, but not necessarily in the order that they appear. So, by deduction you can figure out where a number appears (or doesn't appears) by following the usual rule of Sudoku ( each row, column and region must contain the number from 1 to 9 once) you can complete a puzzle. This particular Sudoku variant challenges the solver with great variety. Each puzzle in this book should stimulate your brain. This book is for those who sometimes seek more challenge than the conventional Sudoku. So, it is time to take the Outside Sudoku challenge "