Edo is a child prodigy, world famous, top-ranking professional Duelist. He is adored by fans around the globe, and his celebrity status has done wonders for the game by introducing it to the masses. He is the anti-hero counterpart of Judai and uses "Destiny HERO" cards to duel. Aster is stated by Pegasus J. Crawford, the creator of Duel Monsters to be one of the best Duelists he has ever seen, listing him along with Yugi Muto, the previous King of Games and Seto Kaiba. He is also a pro-athlete, and excels at skiing, skydiving, skysurfing, and surfing.

Spoiler

Though not initially caring much for Judai and Duel Academy, Edo is sent there by his manager Takuma Saio to defeat Judai, succeeding in doing so. It is only after a furious Duel between Heroes and realizing that he was being deceived that Aster comes to better terms with Jaden.