As with the other Ultras Arufon'nu was once a humanoid born on the planet that would be known as the Land of Light. When the Plasma Sun was activated she and the other members of the Silver Cross Corp, healed who they could. She was a member of the Silver Cross Corp and a friend of Ultraseven and Zaji. When Seven brought the wounded Miclas from planet Buffalo, Arufon'nu healed the kindly creature. She later left with Seven, Zaji and other Silver Cross members to help Ultraman after his battle with the Baltans.
Later, she went with Seven to visit ancient Planet Earth. The two found themselves garments and went to explore, planning to meet up with Zoffy who had also joined them on-world but in another region. They had come to Earth on the info provided to them by Ultraman who was wounded from battling the Baltans, the beings who had meddled with the Plasma Sun and created Ultras and monsters alike. The Ultras had learned that the Baltans had sent numerous monsters they were experimenting to Earth for their experiments.
During their stay they noted how planet Earth was so much like the Land of Light was before the need for the Plasma Sun. Their sightseeing was cut short when a wild boar burst out of the bushes and attacked them. Seven was wounded and when the boar appeared to charge again they were saved by the native humans who were hunting it.
The primitives noted Arufon'nu's power of healing when she helped Seven and invited the pair to stay the night in their village. As the chief's son stepped out that night, the two followed him, out of concern for his safety. They were relieved that he was only going to relieve himself but that all changed when Gomora appeared.
Arufon'nu did not battle the giant monster, instead she stayed on the side lines as Seven battled the dinosaur like monster. In the middle of the fight the village chief appeared revealing he had seen what was a rocket land on Earth, releasing vast numbers of monster in larval form into the world.
After defeating Gomora, Seven and Arufon'nu traveled the land coming across some ruins, where in Seven disappeared for a short time. Eventually they met up with Zoffy, but were all attacked by Geronimon and his army revived monsters. Arufon'nu transformed with Seven and Zoffy, while she took down a monster, she was attacked by Telesdon and it fire breath. Saved by Seven, Arufon'nu reverted to human form, to injured to again transform, although not so much that her life was endangered. She later chose to stay on Earth, while the other Ultras continued their journies.
- Unnamed Attack: An unnamed attack, Arufon'nu places her hands beside her color timer and extends them outwards creating a diamond shaped beam that incinerates the target.
- Healing: As a member of the Silver Corp, Aru can heal others with light, so long as they are organic creatures, seeing how she healed Miclas. She can even use this power in human form and it is respected among the healers of the Silver Cross.
TransformationLike the other Story 0 Ultras, Arufon'nu uses Plasma Ore, special material irradiated by the Plasma Sun, to transform. In her case she uses a Necklace. To transform, she places her hands beside it and by her will she is transformed into her true Ultra self. Arufon'nu did not posses a human host, instead, like the other Ultras of her continuity, she was born with her own natural human form which she uses.
- Arufon'nu is the first instance of an Ultra losing his or her powers.
- Besides Mother of Ultra, Arufon'nu is the first named member of the Silver Cross Corp