Here are enough tough puzzles to test your mental powers for hours and hours. Try this never-ending array of puzzles, challenges, funky facts, things to build,
A collection of brain teasers, puzzles, optical illusions, IQ tests, trivia challenges, and math tests designed to help people improve their brain power.
Test your powers of thinking with over 500 challenging problems and puzzles. Here, Mensa presents a collection of problems that require either logical deduction