After proceeding for a moment, Xu Yang arrived at the entrance to an underground fissure. Waves of ghostly qi seeped out from within, and quite a few Yin Souls and Corpse Ghosts stood around it. Yin Souls were formed when the souls of humans and Monster Beasts absorbed ghostly qi after death.
Pure souls would mostly head for the legendary cycle of reincarnation to be reborn. Though no one could prove that reincarnation truly existed, it was still a source of hope. Once a soul was tainted by ghostly qi, it was no longer pure and would swiftly transform into a Yin Soul. These Yin Souls possessed no memories of their former lives and had become new beings, devoted to absorbing the yang qi of the living. They were not tolerated by righteous cultivators.
Corpse Ghosts, meanwhile, were another kind of ghostly creature. They were formed from living beings...