Taiyi Zhenren is referenced rather than seen in Jackie Vs. AI. He Xian'gu tells Jackie, in the long hallway after the dining hall scene, that the body Jackie is currently inhabiting is on loan from the lotus, and that the master who arranged the loan still keeps the receipts. Jackie laughs because he thinks she is joking. She is not joking. The implication that runs underneath the entire book is that the four divine weapons are recoverable by Jackie precisely because Taiyi's reassembly bound them to the lotus-body across all its incarnations — so the cast-iron spatula in the kitchen drawer is not pretending to be the Fire-Tipped Spear; it is one, by the older accounting.
In Chapter 19, when Jackie finally holds the Universe Ring, the narration pauses for one sentence — 'Somewhere a master who had not been mentioned by name closed a small ledger.' That is Taiyi. He is the bookkeeper of lotus-bodies, and the ledger closes when the last weapon is back in the right hand.
Taiyi Zhenren appears in Investiture of the Gods (16th c.) as one of the twelve Golden Immortals of the Chan school of Daoism, residing on Mount Qianyuan in the Golden Light Cave. He gives Nezha the Red Armillary Sash and the Universe Ring as toys when Nezha is born, then takes responsibility for him after the seven-year-old kills the third son of the East Sea Dragon King. When Nezha returns his flesh to his mother and his bones to his father, it is Taiyi who travels to the underworld to retrieve Nezha's wandering soul and assembles the lotus body — three flowers for the three souls, lotus leaves for the limbs, lotus root for the spine.
His name means 'True Person of the Supreme Unity.' In Daoist cosmology Taiyi is also a star, the polar one — the unmoving point around which the lesser stars revolve. The mastership of Nezha is therefore not metaphorical: Taiyi is the fixed reference by which a lotus-body knows it is the same boy across deaths.
Compassionate reassembly. The first act of the master is not to teach but to put a child back together after the child has chosen to come apart — the lotus-body is the prototype for every second chance in the Chronicles.
Bookkeeper of incarnations. Taiyi keeps the ledger that links Jackie's body to Nezha's; the weapons recognize the hand because the hand is on file.
The Polar Master. His name is a star that does not move — the fixed reference Daoist seekers orient by, the off-screen authority the books trust to hold the line.