On the other hand, unknown to Assassin, her Ichor of Reverie: Zabaniya, which manipulated her targets with song beyond the realm of human hearing, surpassed its original in power.
Against a large group, as she had used it earlier, its effects ended at jolting her targets’ brains and causing their magic circuits to go out of control, but if she concentrated her “song” on a single person, it was capable of bringing the average Servant to their knees, or completely dominating a human brain. The original had not been so powerful. Even if she had known that, however, she would not have accepted it. As far as she was concerned, the instant she had worked it out with her own power, it was an irreplaceable, divine work.

Fate/Strange Fake: Volume 2, Chapter 5 ("Day 1, Dawn")