He had been dead for ten years and stayed in the underworld for ten years.
A ghost without a physical body finds cultivation extremely difficult, as they must first resolve the form without a physical body; otherwise, they will be dragged into the hands of a Yin Messenger by hell.
The underworld authority in the West Bull New Continent does not cover the entire underworld, making it perilous for ghosts. Various ghost monsters and Ghost Gods may use wandering ghosts as food, and they could also be used to cultivate treasures like the Resurrection Lotus.
The difficulty for a ghost to survive is immense. During those ten years, not only did Chen Shi survive, but he also subdued a large group of demons, disasters, and calamities, even to the point that Chen Shi found it unbelievable.
Little Dun Fairy was perplexed about another matter, saying, "Why did your grandfather seal the memories of that period of your time?"
