"Mahou Kishi Rayearth is a role playing game for the Sega Game Gear. Published by SEGA and released on December 16, 1994, Magic Knight Rayearth is a short RPG based on the manga/anime series of the same name. It follows an alternate story-line where Mokona runs off and the three girls have to find them."
More info and download link: http://www.romhacking.net/translations/3726/