“You know, I was actually planning to prepare all sorts of things for you, too. Blackbeard’s treasure, that Paracelsus guy’s flask, the hero Spartacus’ manacles... But then I had a little idea. I wondered what would show up if we let the city choose the Heroic Spirit, with no catalyst at all. I wondered what could possibly be drawn by this chaos.”
She did not know what would happen. With an ecstatic smile on her face, his employer went on narrating the folly of willingly embracing such an uncertain element in a bright, clear voice.
“It’s set up so Ruler won’t come, but there’s always a chance, right? Still, even without a catalyst, it’d probably just end up being a hero with a similar nature to the summoner.”

Fate/Strange Fake: Volume 3, Interlude ("The Passion of the Nameless Soldier")