|Gender||Unknown (Assumed Male)|
|Character Type||Staff NPC|
There is little known about Ra Mu. Ancient South American records describe a being of immense power being worshiped by a lost tribe of human beings calling themselves the Mu, though most historians will dismiss these as part of a Nanska tribal myth.
During the Wily Wars, Dr. Wily unearthed a strange alien computer that identified itself as Ra Moon, though this may have been a mistranslation on the part of Wily's laptop software. When awakened, Ra Moon created an electromagnetic wave field that threatened to shut down all electronics on the planet in a massive blackout: Only Rock, Blues and a handful of Robot Masters were spared the effects through a special armor coating applied by Dr. Light. Ra Moon demonstrated the capacity to gain access to information stored on any computer it came in contact with - allowing it to instantly recreate several of Wily's Robot Masters, with programming and memories intact. While Wily was attempting to study Ra Moon's technology and create a Super Wily Number from what he learned (Ra Thor), Ra Moon was learning everything it could from Wily, using his Devil designs to create its own Ra Devil. Wily soon found himself in over his head, as Ra Moon declared its intentions to bring Earth under its control, turning Wily's Ra Thor against him and capturing him in his own laboratory. Rock, alongside the recreated Wily Robot Masters, was able to defeat Ra Moon. Damaged, the angry machine began to collapse the ancient temple around itself, leaving Wily, Rock and the Robot Masters barely able to escape with their lives. Ra Moon's energy field dissipated shortly after, leaving Earth with only a forty-eight hour EM blackout in its wake. Attempts to locate Ra Moon since then have proved futile.
Comparative studies done between recordings of Ra Devil and the Stardroid's Dark Moon devil have revealed a similar structure and composition, drawing theories that Ra Moon was a Stardroid or Stardroid creation.
Dr. Orihime Vega, a researcher from the Tanabata Kingdom, has done extensive research into Mu mythology and relics.