Luna is the Signer associated with Ancient Fairy Dragon. The "Ancient Fairy Dragon" card was in possession of the Dark Signers, until Luna defeated Devack with Leo's help and claimed the card back. The only other humans that have come in to contact with her are Jack Atlas, Tetsu Trudge, Yusei Fudo and Leo.
5,000 years ago, Ancient Fairy fought with the other Signer Dragons in the battle against the Earthbound Immortals. The dragons managed to seal the Immortals within the Nazca Lines, but Uru grabbed Ancient Fairy Dragon with its web and dragged it into the earth with the other Earthbound Immortals.
Sometime later, Ancient Fairy Dragon became the ruler of the Duel Monsters Spirit World (though it is not explained in the series how she ended up there) and kept watch of the spirits that resided there. Regulus the white lion is the servant to Ancient Fairy Dragon.
In the twenty first century, Dr. Fudo created "Ancient Fairy Dragon" and three other Signer Dragons as Duel Monsters cards to be used as key cards for the reactors of the Old Ener-D. After Roman Goodwin betrayed him, he dropped "Ancient Fairy Dragon", which then fell into Roman's possession, until he gave it to Devack.
When three-year old Luna entered the Spirit World, Ancient Fairy Dragon watched over her, too. She warned Luna of an evil that threatened the land and had Luna promise that she would protect it. Unable to cope with the responsibility, Luna broke her promise and returned to her own world.
At the age of eleven, Luna returned to the Spirit World. She encountered Ancient Fairy Dragon in the Ancient Forest, which has been destroyed by Professor Frank. Ancient Fairy Dragon managed to move around while in her prison and seized Frank. As she proceeded to attack Frank, Luna managed to force her Duel with Frank into a DRAW, returning herself and Frank to their world and saving Frank from the Dragon's angry spirit.
While Luna is held captive by the Arcadia Movement, she communicates with Ancient Fairy Dragon for help. Although Ancient Fairy Dragon is unable to help, she says her servant Regulus will help Luna, in the hopes that Luna will join forces with the white lion to free the Dragon's spirit.
During the present day battle between the Signers and Dark Signers, Luna travels to the Spirit World to save Ancient Fairy Dragon. Luna, Regulus, and Torunka manage to convince Zeman that the only way for him to minus Ancient Fairy completely is to release her first, and then place the Curse on both the Dragon and Regulus. The Ape King is easily deceived and begins to release Ancient Fairy Dragon.
However, Zeman eventually finds out they were trying to trick him and orders his army to attack them. Fortunately, he is killed by Regulus at the same moment Leo defeats his Duel Monsters counterpart that was being used by Devack in the human world. Torunka then sends Luna back to the human world, so she can take her brother's place.
Devack Summons "Ancient Fairy Dragon" with "Cursed Prison", which keeps her chained and caged. Luna takes Leo's place in the Duel and forces him to sacrifice the dragon to prevent the destruction of "Earthbound Immortal Cusillu". Luna then uses Leo's "Respect Synchron" to revive "Ancient Fairy Dragon" back to the twins' side of the field. As this occurs, Regulus appears to shatter the bindings of his Mistress. Luna then proceeds to activate the dragon's effect to Destroy the Field Spell Card, "Closed Forest", negating all the effects of "Cusillu" and rendering it useless. Luna attacks it with "Power Tool Dragon" and "Ancient Fairy Dragon" to destroy the "Earthbound Immortal" and defeat Devack.
After the Shadow Duel ends, Ancient Fairy Dragon and Regulus both appear as spirits not only to Luna but also to Leo, Yusei Fudo and Tetsu Trudge too. Ancient Fairy Dragon thanks her and informs her that the spirits used to Summon the "Earthbound Immortal" have all been returned to the spirit world. After stating that they will support Luna in the fight against the Dark Signers, Regulus and Ancient Fairy Dragon materialize into Luna's hands as Duel Monsters cards.
After Leo Summons "Power Tool Dragon" and "Ancient Fairy Dragon" in an attempt to protect Luna from Aporia, he died due to the device attached to his heart by Aporia. Ancient Fairy Dragon called out to him, telling him that it wasn't yet his time to die and that he is the one that must save Luna. The effect of his "Morphtronic Lantron" activates, and he is revived with a mere 100 Life Points. After the Crimson Dragon's seal appears on his back to bestow him the Heart mark, Ancient Fairy Dragon tells Leo that he is the sixth Signer and that all she wants is for Luna to be safe forever.
Reverse of Arcadia
Ancient Fairy Dragon appears as a Single Duel opponent. She can be unlocked during Story Mode, by clearing chapter 4.
In Yu-Gi-Oh! 5D's World Championship 2010: Reverse of Arcadia, Ancient Fairy Dragon uses a Field Spell Deck based around her own card, titled "The Ancient World".
- Yu-Gi-Oh! 5D's episode 113: "Burning, Seething Soul! Scar-Red Nova Dragon"
- Yu-Gi-Oh! 5D's episode 30: "Fight or Flight"
- Yu-Gi-Oh! 5D's episode 19: "Return to the Spirit World, Part 2"
- Yu-Gi-Oh! 5D's episode 37: "Digging Deeper, Part 1"
- Yu-Gi-Oh! 5D's episode 47: "Mark of the Monkey, Part 1"
- Yu-Gi-Oh! 5D's episode 63: "Signs of Doom, Part 2"