Challenging Puzzles

Charge up your cognitive power with these challenging conundrums! Featuring more than 200 illustrated, full-color puzzles-- including sudoku, logic problems, riddles, Latin squares, visual teasers, and math challenges--this collection lets you exercise your mind, whether you've got five minutes or an hour. The fun begins with moderately difficult brainteasers, but solving gets progressively harder as you go along and your skills develop.