Jack - Turn into anything

After leaving the park, Flat decided to test Jack’s power of “transforming into anything,” making him turn into everything from people to plants and animals, and then eventually inanimate objects. At first, he thought, “there’s no way Jack the Ripper’s true identity was an inanimate object.” But according to Jack, there were apparently many romance novels in which “Jack the Ripper was actually a person possessed by a cursed item,” and then he had shown Flat how he could transform into a surprising variety of objects.

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Fate/Strange Fake, Volume 1, Chapter 1