Unlimited Blade Works, the second of Fate/stay night’s three distinct narrative routes, concentrates on the concept of the struggle between oneself and an ideal.
It’s a story with an altogether different feeling to the Fate route, featuring a great deal more internal conflict. And not just for the protagonist Shirou Emiya, either, but also for many of the people around him — most notably heroine Rin Tohsaka.
In fact, this time around, it’s only really Saber, who had plenty of her own struggles in Fate, who gets off relatively lightly (in terms of mental and philosophical challenges, anyway — though she does spend much of the story being physically and sexually tortured). Everyone else has a lot of very serious and meaningful questions to try and answer before the two weeks in which the story unfolds come to a close.