Killer Sudoku is the most challenging of the Sudoku variants. Some see it as the most pure form of number/logic puzzling. You start with no numbers filled in on the grid and you must use logic and simple addition to fill in all the numbers. The original rules of Sudoku apply: each column, row and 9x9 box must contain the numbers 1 to 9 once only.
Tim Dedopulos is an author, puzzle setter and editor. He worked for Wizards of the Coast and White Wolf, and has written role-playing games and fantasy fiction. He wrote The Ultimate 1001 Puzzle Book and The Greatest Puzzles Ever Solved (both Carlton). He lives in Westminster, central London.
This book contains more than 150 challenging Killer Sudoku puzzles that vary in difficulty from nice and easy to downright devilish! Full instructions, tips and solutions are included.