The Yin Qi just now had been saturated with resentment, chilling everyone to the marrow.
Although Iron Mountain Tiger and the others could not see it with their naked eyes, they could sense that the Yin Qi seemed to contain some unknown aura of evil spirits.
Under the cultivation system prescribed by the Dao Court, ordinary cultivators generally had almost no means of defending against such invisible Yin and evil entities.
For the past twenty thousand years, the cultivation world had been peaceful, the common people had multiplied, the Demon Sect had retreated into hiding, and evil spirits had avoided the light.
Under the bright blue sky and broad daylight, the vast majority of cultivators would never encounter invisible evil spirits in their entire lives. Even if they did, they could not see those Yin entities with the naked eye.
If the eyes could not see it, they treated it as though it did not exist.
The divine thought of ordinary cultivators likewise found it difficult to "perceive" evil spirits.
Thus, most cultivators in the world knew of Demonic Cultivators and Demon Cultivators, yet had no clear conception of invisible evil spirits, Yin ghosts, or gods.
Iron Mountain Tiger and the other three were somewhat different from ordinary people.
They were tomb robbers who dealt with things beneath the earth year-round, so they more or less believed in "evil."
They knew that there were terrifying ghosts in this world that could neither be seen by the naked eye nor sensed by divine thought.
And they were not even Earth Ghosts.
Though Earth Ghosts were called "ghosts," they were ultimately still "tangible."
What was truly frightening were certain "ghosts" that had transcended bodily form and become formless.
Because they were formless, unseen, and imperceptible, no one could know just how terrifying