Yu-Gi-Oh! 5D's (Anime)
Dark Signers arc
During the fight between the Signers and the Dark Signers, Luna goes to the Spirit World, where she finds Regulus, in order to free Ancient Fairy Dragon from the seal she has been put under. Eventually Luna is able to find the White Lion in Pojar Forest with the help of a spellcaster spirit named Torunka. However, Regulus doesn't act too friendly with Luna or anyone else for that matter. According to what Torunka told her, Regulus is dealing with the issue of not being able to save Ancient Fairy from her Rock Stone sealment. Its behavior is also being caused by the effect of the Cursed Needle around its ankle.
She tells the Lion of the promise long ago made to Ancient Fairy, however because of the cursed instrument, he understands her on the opposite way. After some following events, Luna is finally able to dispose of the Needle and convince the White Lion of her righteous intentions by showing him her Mark of the Dragon. Luna learns that Regulus is actually the one who called for her as he had already heard of her existence long ago from its master and as such, has been fighting ever since waiting for Luna's return to the Spirit World. Regulus tells her that the one responsible for Ancient Fairy Dragon's sealing is none other than King Zeman.
In order to set her free, Regulus, Luna and Torunka set off to Zeman's castle. They are able to get inside by tricking Zeman into thinking they are servants and have captured an "unsuspecting" Regulus. Also they make Zeman believe that the only way for the King to minus Ancient Fairy completely is to release it first and then place the Curse on both master and servant, thus to that deceitful reason the Monkey King completely falls for.
Torunka accidentally reveals the plot, resulting in a chase and the group getting separated. The two find Regulus after he destroys Zeman. Luna is taken back to the real world to take over for Leo, and after she plays "Respect Synchron". Regulus jumps to the real world briefly to free Ancient Fairy from her chains, then goes back. He later becomes a Duel Monsters card for Luna to use in her Deck as a way of repaying her.
World Racing Grand Prix arc
Regulus shortly appears along with Kuribon in the forest outside Haley's house, as they are worried for Luna who has been guided into the forest while being in some sort of trance.
He shortly appears to aid Luna, after she gets blown by an attack made by Lester to her Bird of Roses. As Regulus appears flying and just in time to catch her and land her back safely to the riding lane. After Machine Emperor Skiel is summoned, Regulus appears before her and warns Luna of the power Lester posesses. Later in the Duel, Lester commands Skiel to attack Luna directly. The spirits in her Deck take the brunt of the blast and Luna skates out of the smoke unharmed. She thanks Regulus and the spirits for their help.
Ancident Fairy Dragon
- He does not appear in the manga.
- Japanese : Rintaro Nishi
- English : Dan Green
all information on Regulus (Character) came from http://yugioh.wikia.com/wiki/Regulus_(character)