Taken from Gods Eater Burst's database:
First spotted during Moon in the Welkin mission. A new type of Aragami, with a jet black body and evil-looking face. Possesses both a powerful electric shock attack and an iron-tight defense mechanism. Worthy of being known as the emperor of Aragami. Origins unknown. When enraged, its entire body goes rigid: but if its cape-like organ is destroyed, that part gets soft, and defenses go down. Try to take it out with a crush type gun.