Killer Sudoku

Telegraph: Killer Sudoku 2

Mensa Killer Sudoku

More than 200 of the most difficult number puzzles

Killer-Sudoku 3 - schwierig bis extrem

Puzzle Book for Adults: Killer Sudoku, Kakuro, Numbricks and Other Math Puzzles for Adults

400 classic Killer sudoku 9 x 9 HARD - VERY HARD + BONUS 250 Hidoku puzzles

Sudoku with Hard, Very hard levels puzzles and a Hidoku 9 x 9 very hard levels

Killer-Sudoku 4 hardcore

Killer-Sudoku 5 - mittel bis hardcore

KILLER-SUDOKU 8 - extrem bis ultra

Killer Sudoku Samurai

65 puzzles

Killer-Sudoku - Samunamupure

Killer Sudoku 1: The Deadly New Dimension

Telegraph Killer Sudoku 1

Killer Sudoku

Scary Sudoku - 300 Freakish Puzzles. Not for the faint hearted: 300 of the scariest, killer Sudoku puzzles. They'll freak you out.

Will Shortz Presents Killer Sudoku

200 Hard Puzzles

Revenge Of Killer Sudoku 2: 150 Killer Sudoku Puzzles

Zero Killer Sudoku

101 puzzles: Maximum Challenge

Killer Sudoku and other puzzle variants

Revenge Of Killer Sudoku: 150 Of All New Puzzles

Revenge of Killer Sudoku 5: 150 puzzles

Revenge of Killer Sudoku 4: 150 Of All New Puzzles

Killer Sudoku Compendium: 101 puzzles of various deadliness

Revenge of Killer Sudoku

Killer Sudoku: 100 Killer Sudoku Puzzles

Killer Sudoku Pro: 200 Puzzles

Killer Sudoku Zero: 200 Puzzles

Jigsaw Killer Sudoku: 200 Puzzles

Killer Sudoku Pro Zero: 200 Puzzles

Mystery Killer Sudoku Pro: 200 Puzzles