The True Dragon Transmutation Method was an exquisite cultivation method, but its name was definitely deliberately embellished. After all, unless one took the third method, consuming numerous strands of unrefined lifeforce, how would one refine essence blood enough to produce a trace of a True Dragon's bloodline aura?
One would have to excavate deeply into the dragon's blood, hoping to bring forth its hidden ancestral lineage. According to the method itself, Anu and the other draconic lineages were considered beasts, but True Dragons and those of equal lineages weren't referred to as such. They were called Divine Myths of Heaven.
They weren't beasts, but existences that predated beasts. They might be gods of some higher form of existence, a greater world like the rumored realm of immortals mentioned in stories and folklore. But Wei Wuyin didn't feel like a god, likely because his bloodline level was far too low.
