- Regulus is the servant of Ancient Fairy Dragon. He assists Luna in her mission to free Ancient Fairy Dragon, who has been sealed in stone by evil forces that threaten the Duel Monsters Spirit World
- See also: Regulus (character)
- In episode 51 after Devak is defeated, Regulus appears as a card, which Luna collects.
- In episode 78 Luna summon Regulus and activate Ancient Sunshine to removed her Ancient Fairy Dragon from her Extra Deck from play to inflict 2100 damage to Lucciano. However Lucciano activate Infinity Force to reducing the damage from Ancient Sunshine and destroying her Regulus.