They're tough, they're tricky, they're thought-provoking...and they're almost impossible to solve! And that's why people who love puzzles will snatch up this Mensa-level collection to assess their solving skills. It's the ultimate challenge, the best test of mental agility and stamina ever. The brain-wracking selection includes logic problems, lateral thinking, mathematic computations, word games, pattern and theme recognition, and conundrums. Some...