Almost a year later, Mayuri appears at a captain's meeting where he and Akon explain what they know about the Quincy group known as the Wandereich. Furthermore, Mayuri confirms that he ordered his squad to slaughter the 28,000 people in the Rukon to stabilize the Wandereich slaughtering Hollows while getting into a debate with Head Captain Yamamoto Genryusai over whose fault that such a deed needed to be carried out. Mayuri is further livid during the Wandereich's attack on the Soul Society when his fellow captains' lost their Bankai as a result of deciding to act on their own before he could completed his analysis on the enemy. Following the first invasion, meeting with Ichigo to discuss his broken Zangetsu, Mayuri locked himself away to continue his research on the Wandereich's Bankai stealing abilities with Urahara offering his assistance on the matter to develop a countermeasure to give the Soul Reaper captains who lost their Bankai an advantage. During the second Wandenreich invasion, Mayuri personally gets involved once interested in the abilities of Giselle Gewelle to turn living Soul Reapers into her zombie slaves while unveiling his own personal fighting team in the revived Arrancars Dordoni Alessandro Del Socaccio, Cirucci Sanderwicci, Luppi Antenor, and Charlotte Chuhlhourne. When Toshiro Hitsugaya appears as Giselle's zombie slave, Mayuri takes on the fellow Soul Reaper captain with the intent to test some of his serums on the youth. But by the time the zombified Rose, Kensei, and Rangiku arrive after Hitsugaya's defeat, Mayuri revealed that he devised a serum to alter the blood of the zombified Soul Reapers so they can only obey him. After having Giselle killed, while restoring Hitsugaya and Rangiku to normal, Mayuri takes Rose and Kensei to aid Byakuya in his fight against PePe Waccabrada.