The Fundamental Virulence

Soldat swarm the occupied Seireitei as lieutenants like Iba, Hinamori, and Isane struggle to survive. Bazz-B fells Hitsugaya, and Cang Du drops a wounded Rangiku beside him, activating the captain's own stolen Daiguren Hyorinmaru to kill them together. In Mayuri's hidden lab, Urahara appears through a Senkaimon, announces he has found a way to recover the stolen Bankai, and produces black pills he calls Shin'eiyaku. He reasons that because Arrancar Resurreccion resembles Bankai, Quincy should be able to steal it too, yet none have, meaning doing so must carry a hidden danger.

Urahara and Mayuri conclude that Quincy have no defense against Hollows, which act as poison to them, so a Shinigami who briefly borrows a sliver of Hollow power turns their Bankai toxic to any Quincy holding it. Distributed across the battlefield by a communication spell, the pills let captains and lieutenants reclaim their weapons. Hitsugaya's ice wing regrows, weakening Cang, and Omaeda slips a pill to Sui-Feng, who returns fire on BG9 with Jakuho Raikoben. Hitsugaya then seals Cang inside a great cross of ice, noting the brief Hollowfication mask over his eye.

Across the ruined city, Shinji uses his reversing Bankai to make Soldat slaughter one another, Ikkaku, Yumichika, and Hisagi are ambushed by the boastful Mask De Masculine, and Komamura crashes down to shield Shinigami from the explosive Bambietta before Shinji takes over with Sakanade. Losing their stolen Bankai forces several Sternritter, Bambietta among them, into their Vollstandig forms, and Yhwach warns that true despair now begins. Far away in the Soul King Palace, Ichigo presses forward through crushing pressure and receives fractured visions of the Soul King's making, briefly gaining extra pupils in each eye.

Urahara reveals the Shin'eiyaku and its ability to make reclaimed Bankai poisonous to Quincy. Hitsugaya recovers Daiguren Hyorinmaru and defeats Cang Du, while Sui-Feng reclaims Jakuho Raikoben and blasts BG9. Shinji, Komamura, and others turn their fights, prompting the Sternritter to unleash Vollstandig. Ichigo glimpses the Soul King's origin within the Irazu Sando.

The episode adapts chapters 552 through 554 plus part of chapter 559 within the Thousand-Year Blood War arc. The adaptation expanded the lieutenants' struggles against the Soldat, Shinji's slaughter of them, and Ichigo's visions of the Soul King, while trimming some of Yhwach's dialogue about anticipating the Bankai recovery.