If you liked the Derayd manga, the Anime-Planet community thinks you'd like:
Hikaru, Umi, and Fuu are Tokyo schoolgirls with nothing else in common, until one fateful day at Tokyo Tower changes everything: the three are transported to the magical realm of Cephiro, and find that their fates are inexorably intertwined. The sinister Zagato has kidnapped Princess Emeraude, whose will power keeps Cephiro safe, and the three girls are told that they must become the legendary Magic Knights in order to save her. This task will be difficult and dangerous, as Zagato has sent his most powerful minions to stop the girls before they can fulfill their destinies. Protected by an ancient wizard's blessing and determined to find their way home, Hikaru, Umi, and Fuu set out on the adventure of a lifetime
Another CLAMP manga with heavy RPG/swords-and-sorcery influence. Both are about earthlings who get whisked away to a fantasy world and must fight to save it. Prophesies and things of that nature factor in heavily. Rayearth is much more fleshed out, and very shoujo, whereas DerayD is a more typical example of this genre.