Unlimited Blade Works
The game's second route features Rin Tohsaka as the heorine. The first part of the story is similar to Fate route, but soon the major threat turns out to be Caster instead of Berserker.
After being attacked by Rin, Shirou and Rin cooperate and search for Rider's Master. During this time Shirou encounters Caster at the Ryuudou Temple, it is revealed Caster is the Master of Assassin, who was summoned as an incomplete Servant to guard the temple's gate. Their confrontaiton is interrupted by Archer, who has been on much worse terms with Shirou in this route due to conflicting ideals. Also in this route, Rin have many dreams of a hero, Archer, being betrayed by his ideals.
Rider activates a spell to drain the life energy out of its people trapped in the school. By the time Shirou and Rin arrives at where Rider is, they find Rider defeated by someone else. Shinji, Rider's master, runs to Kotomine, who gives him Gilgamesh so he can continue to fight in the Holy Grail War.
Shirou and Rin discover that their teacher, Soichiro Kuzuki, is Caster's Master. During a failed ambush attempt, Kuzuki surprises them with his physical fighting abilities that are further enhanced by Caster's magic. The next day Rin takes Shirou and Saber out on a date, at the end of the date, they encounter Caster. Caster reveals her Noble Phantasm to be a dagger called the Rule Breaker, which she uses to cancel the contract between Shirou and Saber, and forcibly taking Saber as her own Servant. Later Castle also forcibly takes over Kotomine's church, making it her new base of operation.
Archer and Rin leaves Shirou to defeat Caster, but Shirou follows them anyways. During the battle, Archer betrays Rin and Shirou and joins Caster. Rin and Shirou decide to seek help from Ilya, but when they arrive, they witness Ilya and Berserker defeated by Gilgamesh. With no hope, Lancer shows up and offers his help. With Lancer's aid, Shirou and Rin once again confront Caster and Kuzuki. During the battle Archer betrays Caster and takes outs Kuzuki and Caster, but doesn't stop there and tries to kill Shirou as well. Rin makes a new contract with Saber and fends Archer off. However Archer kidnaps Rin and takes her to the Einzbern Castle.
Shirou, Lancer, and Saber go to rescue Rin. It is revealed that Archer is Shirou's future self, and he is trying to kill Shirou to erase his own existence. Shirou and Archer duel while Lancer goes to rescue Rin. When Lancer reaches Rin, Kotomine appears and orders Lancer to kill Rin, in the ensuing confrontation Lancer and Kotomine kills each other, leaving Rin to escape before the room is burned down by Lancer's spell.
While fighting Shirou, Archer remembers his old believes and lets himself to be defeated, and saves Shirou from Gilgamesh. Later Gilgamesh inserts Ilya's heart into Shinji to make him the new vessel for the Holy Grail. That night, Rin and Shirou have sex to replenish Shirou's mana in preperation for the final battle against Gilgamesh.
The next day, Rin, Shirou, and Saber goes to the Ryuudou Template. During the battle between Shirou and Gilgamesh, Shirou uses his Reality Marble, Unlimited Blade Works, to defeat Gilgamesh. When Gilgamesh tries to take out Shirou in a last-ditch effort, Archer jumps in to save both Shirou and Rin once again. With a hopeful future where Shirou doesn't repeat his past mistakes, Archer bids Rin farewell and disappears with a smile. In the Good Ending Rin keeps Saber around and everyone lives happily ever after. In the True Ending Rin leaves to study at the Mage's Association and Shirou follows her as an apprentice.