Divine Body

Officially called Preserved God Bodypart. Fragments of a god.
Those items had already appeared in other entries in several different forms, but The Adventures of Lord El-Melloi II was the one that gave them main focus. They deteriorate if neglected, but if utilized correctly, they can enable Age of Gods’ magecraft, otherwise impossible in the modern era. However, it’s extremely difficult to operate a Diviny Body from a completely different mythology from your ancestry. The main reason why the Clock Tower ignores the eight Divine Body allegedly still functional in Japan is that even if they did obtain them, the idea that they could adequately operate them is implausible.

TYPE-MOON BOOKS material: The Adventures of Lord El-Melloi II Glossary