Yin creatures are formless by nature, making them extremely difficult to kill completely.
Qi Cultivation Cultivators who have not yet opened their Primordial Gate, solidified their Brain God, or learned any Technique and Daoist Skill are typically helpless against them.
This is also why Fierce Ghosts often claim lives in the mortal world, and why Mortals can only seek help from Cultivators.
The charlatan Daoists of the martial world know, at most, a few tricks from the Fire Manipulation Technique. How could they possibly deal with a yin spirit that has gained some power?
Especially in [Fengdu], some ghosts have achieved success in their Cultivation. Turbid yin converges, baleful qi gathers, and they form solid bodies that are even harder than refined iron. They cannot be killed by the blades of Magical Artifacts, making them all the more difficult to handle.
