Serenity transformation (Antiworld) [Mirror Invasion]

For a long time people thought about mirrors like about magic items. But could anybody imagine that there is a hidden world under deceptive-quite surface and it is alike with our world as two peas in a pod, but being absolutely antipodal at the same time? And what will it be if these two worlds clash? Is this the end of the world? How does it refer to Usagi and her friends, and who is this girl in a black dress? You will discover all of these in a fan-made project Sailor Moon: Mirror Invasion.