Due to lack of power and time, Rider forces Saber to leave so they can figure out what to do next. Rider comes up with an idea, but it was only a plan to stall for time for a possible idea to come. Rider will trap Caster inside his reality marble long enough for them to figure out a plan. While Rider is out, Kiritsugu calls Irisviel, which Waver picked up in her steed. Kiritsugu tells Waver to have him have Rider replace himself and Caster under the signal that he will eventually give. He states that this plan will only work if Saber’s left hand is usable, since it will unlock the noble phantasm she carries necessary for them to slay the creature. Of course, her left hand is unusable thanks to the curse of Lancer’s spear, Gae Buidhe. So that they can finally destroy the Caster, Lancer would break his spear in an act of chivalry so that he can fight Saber in the future with her full strength.
Saber regains her power and reveals the sword made invisible by the wind, the Sword of Promised Victory, Excalibur. Unlocking this, however, draws the attention of Berserker as he turns his sights from Archer to Saber. Archer, angered that he turned his back to him, attached Berserker, only to have Berserker destroy his ship with ease as he was not paying attention. Berserker would continue to attack Saber until Lancer was able to get on board the ship and quickly destroyed it. However, Berseker was not done just yet. He carries a machine gun and was about to fire at Saber before Archer knocks him off balance and destroys the gatling gun in the process, causing him to fall to the water. At around the same time, Kariya was nearing the limits of his power, so Tokiomi quickly ended it all by burning him. Kariya would fall from the rooftop and actually survive the fall with a major burnt marks on his body. Kirei was about to finish him off, but decides otherwise and heals him.
This point is where I believe was the highlight of the show: the monologue of Irisviel. Saber lifts up her sword calling for all of the beings around her to hear her player. The life and energy source from the plants, water, and air as well as the wishes and prayers of the past, present, and future, draw together on one spot in one era to answer the calls of the one who wields it all. As the words of the lost voices come together, the the point of a brilliant shine, Saber calls out the name: Excalibur. With one swing of her sword, the prayers of the words materialized into one major shockwave, just in time to cleave Caster perfectly in half. Caster would have one final image of his love for Jeanne D’Arc before disppearing for good.
Not to be outclassed by a well-done CG of the attack, Archer and Rider get one last talk before they leave, commenting on the actions that Saber did. In Rider’s eyes, he still sees her as someone who lives for other’s well-being before herself, much unlike what a true king should be. However, Archer finds beauty in what Saber is doing, thinking that her struggle to answer everyone’s call to the point where it exceeds her limits mystifies him. It is because of their conflicting ideas that Rider believes that they will never get along. This is where Archer would officially fall in love with Saber, stating that no one will love her impossible struggle more so that he will and that Saber is only meant for him to be loved, for that will be law by his accord.