You recall our battle. You were quite vicious. Bestial, even, as I've rarely seen before. As you were made and enslaved, only to fight and to follow orders... such is the lot of Servants. I understand your hunger as others do not.

[Once again, it could easily be read as a criticism against himself. But once again, he does not explicitly refer to himself as so helpless, much too proud, much too stubborn.]

Come to me and show me your potential. Test your blade against me, whenever you feel such ugliness rearing its head. And I will exhaust you, and I will sate you, and I will quell this beast that lives inside. This I do for a very specific price.