FLEX YOUR brain power like never before! From acclaimed author Dr. Gary Gruber, whose proven critical-thinking methods have sold more than seven million books,

Six murders. One hundred pages. Millions of possible combinations... but only one is correct. Can you solve Torquemada's murder mystery? 'If James Joyce and Aga

This is not really a book. This is a building in the shape of a book...a maze. Each numbered page depicts a room in the maze. Tempted? Test your wits against mi

If you're an experienced sudoku puzzle solver looking for a real challenge, then the World's Hardest Sudoku Book: 200 of the World's Toughest Sudoku Puzzles (Vo

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