Can you imagine that puzzles can be fun, games with numbers and letters are very entertaining, and drawings that at first glance seem simple actually hide many mysteries? You think that's impossible? Then we invite you to open the book that you are holding in your hands and make sure otherwise. After all, it contains only the most mysterious drawings, interesting puzzles, optical illusions, which at first simply cannot be explained, and cunning tasks, for the solution of which you need to connect your imagination and non-standard thinking, show ingenuity and resourcefulness. We are sure they will not leave you indifferent. By solving them, you can develop the ability to quickly and accurately count, build logical chains, find patterns, reflect and draw conclusions. Do not miss the opportunity to train your mind!