Returning to Shirō's home, he, Rin, and Saber all decide to avenge Emiya and stop Gilgamesh by destroying the Holy Grail once and for all. Through the use of familiar spirits, Rin deduces that the Holy Grail is being summoned at Ryuudou Temple. She then explains that Shinji, the only other magus participating in the Holy Grail War, would be the only viable candidate as a substitute vessel, as it was apparent Illysaviel was supposed to turn into the Lesser Grail at the end of the war. While devising a strategy to defeat Gilgamesh, Rin realizes Emiya was the only one who could perfectly counter him, since he had the ability to summon a duplicate of any kind of weapon. She then concludes that Shirō needs to master Unlimited Blade Works so he too could be an even match against Gilgamesh. Since he doesn't have the sufficient mana to do so, Rin improvises, performing a ritual that implants her Magic Crest into Shirō, thus allowing them to share their mana storage. During the ritual, Shirō inadvertently taps into Rin's memories, something that embarrasses Rin when she finds out. Afterwards, Shirō finds Saber exploring his house, and she thanks him for showing her the way to her dream. Then, she has him promise that he and Rin will survive the Holy Grail War. Meanwhile, Gilgamesh has finished transporting Shinji to Ryuudou Temple, which summons the Holy Grail.