We could say that now there are lots of different stories for Rayearth: the Anime, the Manga, the OVA and the video-game stories.
Rayearth 1
It started on October 93 and ended on February 95. It had 12 episodes.
Brief Summary
Hikaru, Umi and Fuu, three junior high school students from Tokyo were summoned to a strange land called Cefiro, which it's peace and order was maintained by the pillar, Princess Emerauld. Since she was 'kidnapped' by Soru Zagato, Cefiro started to ruin itself and monsters started to born and destroy the land. The mission of the three girls is to become Magic Knights by getting the weapons made of Eskudo, reborn the Mashins and 'save Cefiro from chaos and destruction' -- very brief summary uhn?
Rayearth 2
It started on April 95 and ended on July 96. It also had 12 episodes.
Brief Summary
After the first battle, Hikaru, Umi and Fuu are summoned back to Cefiro by an unknown person. There, they discover that Cefiro will ruin within little time. To save Cefiro, they must find a new pillar that would wish the peace and order of Cefiro again, but there appears the troops of the other countries: Autozam, Cizetta and Fahren, which have their own objectives to get the control of the pillar. The Magic Knights, although they do not have to fight, they decided by themselves that they would find a new pillar and battle against those countries to do something for Cefiro. -- another brief summary uhn?
Part 1
It started on October 14th, 1994 and ended on ??, completing 20 episodes for the 1st part. It's themes were 'Yuzurenai Negai' for opening and 'Asu e no Yuuki' for ending. The Anime is longer than the manga because many adventures were added, and some modifications: Zagato's assistant Innova, Presea's destiny and other changes on the battle chronologies.
Brief Summary
The three girls were summoned to the land of Cefiro and have to get the weapons made of Eskudo, develop them according to the girls' heart and mind, revive the Mashins to finally battle against Zagato to help the Princess to get her wish realized.
Part 2
The 2nd part started on ?? until ?? (sorry, I forgot... T_T), completing 29 episodes and one year of Rayearth series. It have four themes: 'Kirai ni narenai' and 'Lullaby -Yasashiku Dakasete- for the first opening and ending, and 'Hikari to Kage o Dakishimeta mama' and 'Itsuka Kagayaku for the final opening and ending. The Anime and Manga versions are very different, which includes some more intensive fights against the three countries, the fight with Nova, Mira becomes a secondary characters, instead of girl A from the first part, and many of the destinies are changed in the Manga because of the Anime's ending...
Brief Summary
Autozam, Cizetta and Fahren are invading Cefiro to get the 'Pillar System' for their own sake. The three girls, summoned by an unknown person, decide to fight for their own spirit and mind. But then, one more unknown country comes to destroy Cefiro: Debonair and her (kind of) daughter Nova, attacks Cefiro with their monsters, powerful than Cefiro's ones, and the Mashin for Nova, Regalia.
It's a differen Rayearth version from the others, with a completelly different storyline. As it says, it was released on video on July 25th 97, the second one on September 26th and the last one, on December 10th, completing 3 episodes.
Brief Summary
The three girls now study on the same school, but are still good friends. But they now have to separate from each other for their parents' decision. The three girl then promise, under the legendary cherry tree, to be friends even far away from each other. But the other world Cefiro, for their own sake, starts an invasion to Earth. Clef, believing in the three girls friendship, gave them the destiny of Earth, joining their powers with the Mashin of RayEarth.
For more information, visit the OVA page.
Saturn
Well, I do not have much information on this one's because, even though I have the game, I don't have a Saturn (weird, isn't it?)
Super Famicon
SuFami's one is like a fusion of the Manga and the Anime Rayearth in one game. Actually, the main storyline is the same as the Anime's, which has Innova, but they use the Manga magic names, kind of Kurefuto, or Araia and other points of the storyline. And there were some additions, kind of Rafaga, Ascot and Caldina joining your party to help you out, instead of just one fight against them... I'm thinking of doing a page related to those, but it's still uncertain...
Game Gear
No ideas, since I don't have a GG, nor the game, even somebody who have both!
Game Boy
Rayearth 1
It is kind of an addition to the manga story. It has totally three main stages, and each girl has one stage to fight on. it's an RPG game, and you fight monster on one VS one fights and you recover magic and life while walking around the stages.
Brief Summary
During their way to find the Mashin, Hikaru, Umi and Fuu find a picture n the middle of the forest. When they discover that the picture was made by Zagato, they are transported into the picture, leaving Mokona alone. Inside, they get separated from each other to fight alone on their own stage story. Hikaru, who appears on a small village, helps them to fight the monsters and to get back to Cefiro, she must end with the monster leader of the area. Umi, who appears in the middle of a forest, finds a weird bunny, not Mokona, and helps an old tree to get rid of the monsters from inside him (really weird!). Fuu appears in a tower, and to get back to Cefiro, she must solve the puzzles that appear on each floor until she finds the exit. When completed the three stages, the three get together to fight three Zagatos (I said it was a one VS one fight).
Rayearth 2 - Missing Colors
I don't have the game, nor I haven't sufficient info.