**Kai**, Great Child of the third world Trius, specializes in martial arts and weaponry, excelling in stick combat alongside his spirit companion Bakuzan. After challenging Bucky upon witnessing his abilities, Kai forges a steadfast friendship and alliance, joining Bucky’s quest. His courteous martial artist demeanor blends with emotional sensitivity, often bringing him to tears. Kai proves loyal and combat-reliable against Trouble Monsters and Hail’s forces across worlds. Captured by Joan’s robots in Undicos, he requires rescue by rebels. He later fights in the final battle against Slash at Doedicos alongside fellow Great Children.

**Tartanian** (Filipino dub name for D’Artagnan) is the youngest Great Child, serving in the fourth world Tetras with his spirit Count Bucklet. Initially timid and tearful against Trouble Monsters, he evolves after Bucky’s intervention forces him to confront his fears. This growth peaks when he defeats a Dark Knight manifestation of his deceased father, wielding his father’s rapier and fencing skills combined with Count Bucklet’s power. He then adopts his father’s musketeer attire and rapier, becoming a courageous Tetras guardian. Tartanian reappears in the finale, briefly immobilized by Slash’s forces before uniting against Slash.

**Ali Babah**, Great Child of the fifth world Pentas, partners with the spirit Hibana. Identified as young and gay, Ali Babah’s true gender is revealed to Bucky’s group after they help break a turtle monster’s curse. Later, Ali Babah aids curse-breaking efforts in Hexas and Novas among the Great Children. Like Tartanian and others, temporary incapacitation by Slash’s forces precedes participation in the collective resistance during the climax.