Very serious simulator is not for average minds that will help you develop your mental abilities, and especially - how your vision reacts to the slightest changes. Of course, you guessed it. You're looking for excellence! This is not as easy as it may seem, because at each level, and there are more than a dozen, find differences will become increasingly difficult. For example, the first picture you see the frog and lily flower. Different scales can be on the back of the frog, or the absence of one of the dozens of petals on a flower. Is able to notice?