(Dress of Heaven)
She was formed through Angra Mainyu possessing the remnants of Irisviel von Einzbern's personality in the Greater Grail. Manifested in the Grand Orders, she takes on the persona of Justeaze Lizrich von Einzbern, but can rather be said to be the remnants of the Greater Grail tainted by All the World's Evils, the Black Holy Grail (黒聖杯, Kuro Seihai?), in contrast to the other Irisviel manifesting as a "White Holy Grail."
As the Servants are slain, Irisviel von Einzbern's body begins to deteriorate, with only Avalon's power enabling her to function. After the sacred scabbard is transferred into Kiritsugu, Irisviel is abducted by Berserker and taken to Kirei Kotomine, who interrogates her as to Kiritsugu Emiya's motives. Angered by her answer, Kirei kills her, her body transforming into a large golden goblet. Irisviel's consciousness is subsumed by Avenger, as black mud begins pouring out of the goblet and flooding the room.
When Kiritsugu is drenched in the Grail Mud, Avenger assumes Irisviel's form and personality in order to communicate with him. Kiritsugu is horrified by the revelation that his methods killed more people than they saved and rejects Avenger, killing its projections of Irisviel and Illya. Avenger then curses him to live a life of despair and misfortune, eventually leading to Kiritsugu's death.
In the Einzbern Consultation Room metafictional shorts, Avenger impersonates Irisviel, tutoring T-chan on the basics of the Holy Grail War and ostensibly consoling the vanquished Servants so that they can pass on without regrets, though she takes sadistic delight in driving them to despair - as with Diarmuid Ua Duibhne. She is revealed to be a manifestation of Avenger by Lancelot, and extends her shadow in a manner similar to the Shadow in an attempt to consume him before being stopped by, though this brief contact corrupts him into his Berserker state.
Fate/stay night: Unlimited Blade Works
In the 2014 anime adaptation of Unlimited Blade Works, Avenger manifests before Illya in the form of her mother, telling her that Kiritsugu abandoned them and urging her to seek revenge.
Fate/Accel Zero Order
Black Iri emerges from the Grail after it absorbed five Servants and Zouken Matou used Irisviel's magical energy to hasten its awakening. Seeing her as Justeaze, Zouken compliments her beauty and realizes his role was only to recall her visage. Black Iri devours him after telling him to dream of the ideals that will never be fulfilled then die. She then goes to devour Ritsuka's party, saying five Heroic Spirits aren’t enough to fill her. Artoria Pendragon and Diarmuid Ua Duibhne hold her off while the others escape.
She and Diarmuid struggle against her until the others return after El-Melloi II transferred Zhuge Liang's powers to Waver Velvet. Black Iri is defeated in the ensuing battle and disappears, saying her hand was meant to reach the ends of the stars.
Dark Irsiviel claims to be the incarnation of the Third Magic who shall reach the Root and annihilate all evil. Compared to the original Irisviel von Einzbern, Dark Irisviel is not a false replica, but the real vessel. She is the remnant of Justeaze Lizrich von Einzbern, or rather, a ruined Holy Grail, polluted by All the World's Evils. Even the Souls of five Heroic Spirits are a mere offerings to her, and aren't enough to fill her vessel.
Artoria Pendragon states that Dark Irisviel's Magical Energy density is such, that even if she worked together with Diarmuid Ua Duibhne, Counter Guardian EMIYA (Assassin), and Mash Kyrielight, they would have no chance of victory. Dr. Roman states that losing Zhuge Liang right before she appeared is the reason they can no longer fight. Artoria agrees, saying that if he were safe, they would stand a chance of victory, but the absence of one Servant is critical. Although Artoria and Diarmuid are able to momentarily hold her off while the others escape, Diarmuid rapidly reaches his limits, and Artoria claims Dark Irisviel is stronger than she had imagined. Once the wounded lord El-Melloi II transfers the hero Zhuge Liang from his broke body into Waver Velvet's, the hero is once again able to wield his former strength. After EMIYA, Mash, and him reunite with Artoria and Diarmuid, they manage to defeat Dark Irisviel.
Shimaudon is the character illustrator for Black Iri.
- Fate/Grand Order - Fate/Accel Zero Order, ACT-18: The Fallen Grail