Varanium

Varanium (バラニウム Baraniumu) is a metal that can harm Gastrea.

Description
Varanium is a metal that emits a magnetic field that weakens and, eventually, kills Gastrea; if a Gastrea is placed inside a room full of Varanium, its chances of survival are zero. This metal is used to craft most of the weapons utilized by Civil Security Corporation, such as Black Bullets, swords and spears. The Monoliths protecting the world from Gastrea are also created from Varanium. However, these Varanium-crafted barriers have been said to be of no match to Stage V Gastrea.

Additionally, humans can replace their innards with Varanium, granting them extraordinary abilities.