A premonition of violence flickered across the knight's face. He was about to choose his words of dissuasion carefully when… from the shadows blanketing the rooftop, a grotesque apparition emerged, rising and swaying to a height of about three metres.
Percival instinctively lunged with the butt of his lance, but was a hair too slow. The Knight of the Holy Lance would never be caught off guard by some unknown monster. Its attempt to engulf and digest him was child's play.
However, someone else had moved faster, their attack a blur of motion that pierced the creature. In other words…
"My apologies, Sir Percival. I've already dealt with it."
Five claws extended from his fingers, tearing through the bodies in a hail of strikes possessing divine speed, reducing the newly appeared apparitions to masses of flesh.
"Your Noble Phantasm, I see."
"Nay. My claws merely grow quickly."
A joke, perhaps... no, not at all.
Rider continued without missing a beat.
"This body, you see, is already dead. Ah, no. I wasn't referring to how Heroic Spirits are shadows of the Human Order. Perhaps because I animate this dead flesh, my metabolism is far too high by modern standards. I thought my claws would stop growing once I was summoned as a Servant, but alas..."
He let out a sigh of exasperation. "You see, I'm constantly trying to keep these claws from popping out."
"A fascinating power, Rider," Percival conceded, "and what tremendous speed. I presumed it was a scout sent by Caster before the intermission, but a single blow?"
"I, too, was a warrior once," Rider said as he sat down.

Fate/Lost Einherjar, Chapter 3