As Archer and Berserker continue to battle in the sky, Saber and Rider are forced to retreat from Caster's demon to rethink their strategy. Rider proposes transporting the demon inside of Ionian Hetairoi, where his armies will hold it off as long as they can while Saber and Lancer find a way to finally destroy it. Kiritsugu calls and explains to Waver how they will defeat the demon and tells him to inform Lancer about Saber's Noble Phantasm. Lancer realizes what Kiritsugu means and destroys his Gae Buidhe to allow Saber's wound to heal and fully use her Noble Phantasm. Tokiomi defeats Kariya by burning him with a blast of fire. He falls from the building, and is later found by Kirei, who is on the verge of killing him but decides to heal him instead. Berserker destroys Archer's Vimana, but is drawn by the unveiling of Saber's sword and begins attacking her instead. Lancer and Archer attack him and destroy his jet. With the coast clear, Kiritsugu fires a flare gun to signal to Waver where Rider should transport the demon. With the demon in position, Saber uses her Noble Phantasm Excalibur to finally destroy Caster and the demon while the former has a vision of Jeanne before his death. With the threat over, Rider and Archer discuss whether Saber's life as king was incredible or tragic before both leave, with Rider hoping to duel Archer in the future and Archer now smitten with Saber.

Kirei discovers Risei's body and informs Tokiomi. Kirei is saddened by his father's death, although Archer suggests that his sadness is due to not having had the chance to kill his father himself. Maiya informs Iri and Saber that Tokiomi wishes to form an alliance with them, and Iri agrees to go to the church to discuss the offer. Before the meeting, Tokiomi visits his wife and Rin, giving his daughter a magus book and some wisdom before leaving. During the meeting, Tokiomi suggests a temporary alliance to defeat the other Masters first and ensure that a representative of the three families, not an outsider, will attain the Grail. Iri agrees, but on the condition that Kirei leaves the city and is no longer involved in the War. Tokiomi complies. As they depart, Iri reveals to Maiya that she is the embodiment of the Holy Grail in human form and will soon die to create the Grail near the end of the war. Maiya promises to protect her until that time comes. Meanwhile, Kirei reveals to Archer that his father's dying act was to leave Kirei the remaining Command Seals, restoring Kirei's ability to contract with a Servant. He also tells him the secret reason behind the war: the Holy Grail can be activated only through the sacrifice of seven Heroic Spirits. Thus, even a victorious Servant must die at the end, which is why Tokiomi is reluctant to use his Command Spells, as he needs at least one to force Archer to commit suicide. Furthermore, Kirei still wants to explore his dark desires, and Archer yearns for a more stimulating master. Later, Kirei meets with Tokiomi, who entrusts him with the guardianship of Rin should anything happen to him, and an Azoth dagger as a symbol of his completed apprenticeship. Kirei stabs Tokiomi in the back with the dagger, saying even his own father and master never really understood him. With Tokiomi dead, Archer and Kirei form a new contract as Master and Servant.