|Base of Operations||Vandenreich HQ|
|Spirit Weapon||Reishi Sword|
Thousand-Year Blood WarEdit
Conquest of Hueco MundoEdit
Seventeen months after the defeat of Sosuke Aizen, Yhwach and his army invaded Hueco Mundo and laid siege to Las Noches. The Vandenreich were ultimately victorious, with Yhwach personally defeating Tia Harribel and imprisoning her within his headquarters. They also enslaved several Arrancar and used them as test subjects for various experiments.
First Assault on Soul SocietyEdit
Yhwach and his strongest soldiers, the Stern Ritter, attack Soul Society soon after their conquest of Hueco Mundo. Prior to entering combat himself, Yhwach visits Aizen's cell, and is surprised to discover his corpse. Eon appears and traps Yhwach in the cell for a brief period by confusing the latter's perception of time. While his men battle the captains, Yhwach confronts Genryusai Shigekuni Yamamoto. After Yamamoto kills a doppelganger of Yhwach with his Bankai, Yhwach reveals himself, steals said Bankai, and slaughters the elderly captain.
Soon after this, Ichigo Kurosaki arrives and attacks Yhwach. Unfortunately, Yhwach quickly overpowers Ichigo, but Ben arrives in the form of Feedback to assist the injured Substitute. Feedback unleashes a brutal assault on the Vandenreich emperor, forcing him to use his Blut in order to minimize the damage. He then comments about how Ichigo does not understand his true heritage or the truth about his mother. When Ichigo demands to know what he is talking about, Yhwach declares that he will drag Ichigo back to his headquarters and tell him there. Feedback threatens Yhwach, and the fight resumes. Feedback reveals his ability to absorb reishi, which surprises Yhwach, but it is not enough to significantly damage him, and he reiterates his intention of brainwashing Ichigo.
Before the fight can continue, Haschwalth informs Yhwach that they must leave for some strange reason. Realizing what Eon did to him in Aizen's cell, Yhwach concedes to this and opens a portal back to his headquarters. Ichigo and Feedback try to stop him, but he easily pushes off their attacks, declaring that he will return for Ichigo. Just as they are about to leave, Feedback reveals that he and his comrades destroyed the vandenreich's headquarters and rescued Harribel, which surprises Yhwach. Upon returning to the site, Yhwach and his army are shocked to see that, indeed, their headquarters is in ruins. Knowing that Ben's attack will have serious consequences for the Vandenreich, especially since it means he knows the location of their headquarters and will undoubtedly tell the Gotei 13 and the Royal Guard, Yhwach orders a search for survivors and for the headquarters to be rebuilt.
Now forced to adjust his plans, Yhwach orders his men to begin rebuilding his organization's headquarters. During this time, a newly recruited Uryu Ishida is brought before Yhwach, who asks him to reveal everything he knows about Ben. Unfortunately, Uryu is unable to provide any key information on Ben, having not known him very well. Eon then appears before the surprised Vandenreich and offers to give them more thorough information about Ben. Yhwach is suspicious, but accepts the offer. Eon tells them about Alien X, and the Vandenreich are awed by it, though they quickly calm down when he explains the quirks in the form.
After hearing the rest of Eon's report, a visibly angry Yhwach declares that Ben must be eliminated as soon as possible. Eon reveals that Ben lives in an alternate universe where the Vandenreich cannot reach him, which angers Yhwach even more, but Eon quickly reveals that he can travel to different universes, and thus can take them to Ben's. Bazz B immediately volunteers to assassinate Ben, but Yhwach states that he cannot spare a member of the Stern Ritter at the moment. Eon suggests sending an Arrancar, knowing that Ben would rather try to convince an Arrancar to join him rather than kill it. Yhwach points out the possibility that the hypothetical Arrancar would accept Ben's offer, to which Eon sadistically declares that he has a way of ensuring that the remaining Arrancar will remain subservient to the Vandenreich.
- Yhwach is the main antagonist of Volume II.
- He is the first villain in the series to kill a hero.