Not much explanation need and fun to play: Perfect. In the beginning I thought it is too simple, but then somehow I run into errors, where I automatically copied the pattern instead of mirroring it. It is somehow more challenging than you think. However, it is not super difficult, but I think this is exactly what this game tries to achieve: Being a casual game where you need to concentrate but it is very rewarding, as it is never so difficult that you will not make it. The sound you have chosen is absolutely perfect and supports this feeling of the game.