Sudoku 3: 200 Puzzles: Hard to Extreme

Perfect for sharpening concentration and reasoning skills, here are 200 all-new Sudoku puzzles that build in difficulty level from hard to very challenging. A musthave for every on-the-go Sudoku sleuth!

• Sudoku: Medium to Hard Volume 1
• Sudoku Puzzle Pad: Medium to Hard: 2
• Absolutely Nasty Sudoku Level 3
• Sudoku 3: Extreme to Grand Master (Chronicle Books Sudoku, Sudoku Spiral Bound, Puzzle Master)
• Will Shortz Presents The Huge Book of Hard Sudoku: 300 Challenging Puzzles
• Will Shortz Presents Survival of the Fittest Sudoku: 200 Hard Puzzles
• mental_floss Sudoku: It's the Brain Candy You've Been Craving!
• Sudoku Puzzle Book Extreme Level: Diabolically Difficult Puzzles for Advanced Solvers
• Big Book of Sudoku
• Beyond Black Belt Sudoku: If you have to ask, it's too hard for you. (Martial Arts Puzzles Series)