This brilliant new puzzle collection from the creators of the hugely successful The Mammoth Book of Puzzles and The Mammoth Book of Astounding Puzzles features a cumulative IQ scoring system based on the new Haselbauer-Dickheiser Test for Exceptional Intelligence, recently used to find the world's smartest person. Included are five hundred new IQ puzzles. Formulated in association with the International High IQ Society and covering a broad spectrum, the puzzles range from surprisingly easy to a level of difficulty that will challenge even the sharpest minds. Theoretically, all are capable of being solved mentally in just a few minutes. The puzzles vary from math and logic problems to word games, with the emphasis throughout on clarity of presentation and elegance of answer. The collection is endorsed by the new and highly popular International High IQ Society—the second-largest and most rapidly growing high IQ society in the world, with a membership across seventy-five countries.