60-Second Brain Teasers Pencil-Free Puzzles contains 201 no-pencil-required brain twisters that take one minute or less. These completely original puzzles range from easy to near-impossible!
Featuring 400 Sudoku puzzles, this book contains challenges, levels of difficulty, and varieties of number-placement (and letter-placement) puzzles. It also contains step-by-step instructions, tips and killer strategies from the founder of the International High IQ Society and confirmed Sudoku addict, Nathan Haselbauer.
Over 500 new maths, logic and word brain teasers.