Hueco Mundo civil war! Ulquiorra's death

Inside Las Noches, Patros slips into Aizen's empty throne room to steal the Hōgyoku, only for Ulquiorra to challenge him. Patros rants that Hollows should never bow to a Shinigami and proposes they seize the sphere together, but when Ulquiorra dismisses him, his two accomplices, Menis and Aldegor, ambush the Espada from behind and run him through. Patros deals the killing blow, vows to make Aizen regret empowering them, and departs with the stolen orb, aiming to become king.

In the living world, Urahara heads off to restock with Tessai and a training-weary Sado, leaving Renji, Jinta, Ururu, and the Mod-Souls minding the shop. Boredom reigns until a Garganta tears open and the three traitor Arrancar arrive. The Soul Society strike force stationed in Karakura, Hitsugaya, Rangiku, Ikkaku, and Yumichika, is alerted and moves out. Patros sends Menis and Aldegor to stall the captains, and the two release their Resurrección, Erizo and Jabalí, overwhelming the Shinigami while Hitsugaya answers with Hyōrinmaru and Ikkaku with Hōzukimaru.

Patros tracks the Hōgyoku's user to the Urahara Shop and clashes with Renji, who releases Zabimaru. Outclassed, Renji is battered by Patros's graded energy blasts, but the Mod-Souls hurl themselves in, trapping Patros with illusions, wormholes, and a barrier while Kurōdo mimics Renji. Patros shreds the trap, downs the Mod-Souls one by one as Noba shields them, and levels the lot before the shop with a Level Two blast. In the park where he once crashed, Ulquiorra reappears in Karakura and gazes down without expression.

Patros, Menis, and Aldegor betray Aizen, slay Ulquiorra, and steal the Hōgyoku. They open a Garganta into Karakura Town, drawing the Soul Society strike force into battle. Menis and Aldegor release Erizo and Jabalí against Hitsugaya's group, while Patros overpowers Renji and the Mod-Souls at the Urahara Shop. The episode ends with Ulquiorra reappearing alive in Karakura Town.

This is an anime-original episode, the 136th of the series, and part of the Arrancar arc with no adapted chapters. Its Shinigami Illustrated Picture Book gag has Shinji hand Ichigo a cat mask before a shopping trip so nearby classmates will not recognize him, which Ichigo angrily throws away.