User blog comment:ImperiexSeed/The oldest being, archangel or leviathan?/@comment-174.241.241.40-20130806221402/@comment-5619706-20140118061406

This is not my own claim. It happens to be the show's, described as the Word of God. "Leviathan cannot be slain but by a bone of a righteous mortal washed in the three bloods of the fallen." If you're going to call me on fallacious claims, I'm going to redirect them to the writers.