Magic Knight Rayearth

The three teenage girls who saved a world at great cost return to Tokyo, a little older and much wiser. They assume they’ll never see the magical, troubling world of Cefiro again… when they find themselves whisked back there by yet another mysterious force. But this Cefiro looks different than the one they left, and Emeraude couldn’t be the one who summoned them this time. What if the tragic climax of their first adventure was only the beginning? (Source: Kodansha)

A side story about Mokona's dream.

"The world is a very small place, but for those who know it...it is very, very large. And the world, when it is viewed by those who 'know'— is far larger than just one world can hold!" The famous CLAMP brings back the characters from all their creations for an ultimate showdown in this multi-dimensional tale. This is the story of four travelers, bound by fate and by prophesied future. Sakura is the princess of Clow Country, and possessor of a strange power that promises to change the world. Syaoran is an aspiring archaeologist and her childhood friend. When Sakura is endangered by the plan a certain man has for the future, the princess' memories are scattered across dimensions in the form of feathers, and Syaoran is forced to go on a desperate journey to retrieve them. They are accompanied by Fay D. Flourite, a magician running from the horrible truth of his past, and Kurogane, a rough-mannered ninja trying to get back to his world. However, the ability to cross worlds demands a great price, and each of them must pay the Dimensional Witch with what he or she values most. In order to save his princess, Syaoran must give up his relationship with her. Even if he gathers all of Sakura's memories, she will never remember their past together... But the world is not so simple. The very moment these four made this decision, their destinies are sealed into a tragic course...as everyone in the group has their own secrets. Visions of the future are seen, and prophesies are made. The cruel future which lies ahead reads only of betrayal, abandonment, devastation and anguish.