Hi everyone! We all know that physical exercise makes us stronger and more attractive. But your body muscles are not the only ones that need training: your brain won't develop by itself, you know? If you want to upgrade it, you have to solve different puzzles and riddles, train your attention and ability to make fast decisions. That's why we have made a list of tasks for you to develop your mind. So, here are some pretty hard puzzles and you will surely have some trouble finding the right answers.