At first it was assumed that Muur was nothing more than a legend. They are a set of armor infused with the soul of a werm. When summoned they gain a physical form and become the loyal protector of whoever awakened them. This process repeated itself for hundreds of years until Asher and the gang figured out how to summon Muur. Muur's newest charges treated them more like family than a weapon, and it allowed Muur to open up and show their true self. They are endlessly curious about the world that they have never had the chance to explore. They enjoy experiencing new things, and are open about any questions and observations that they have. Despite all this, they haven't forgotten their purpose. They are still more than happy to strike down anyone they perceive as a threat. Their physical form is a combination of fire, sand, and molten glass. Nobody - including Muur - knows what their armor is made of or the origin of their existence.