The black mist, as if feeling the call of kin, rushed toward the Hell Palace only to find that it had suddenly disappeared. From the aura emitted by the Hell Palace just moments before, it detected the presence of Jiang Tang.
The black mist ceased its attack and submissively allowed itself to be absorbed by Jiang Tang's avatar.
Within a single breath's time, Jiang Tang's avatar had absorbed all the mist, and the feedback from the avatar confirmed that the black mist was indeed a remnant soul of an ancient power.
The emergence of the Hell Palace was due to a remnant soul of an ancient being that had fallen in the Mortal World. Separated by millions of years, the Hell Palace appeared time and time again, casting spells to awaken this sliver of the ancient being's soul.
Before the ancient power started practicing demon art, his nature was kind. This remnant soul that awoke in the Mortal World, tracking and attacking people, was just an act of consciousness seeking the Hell Palace.