This story has many omissions, but it generally explains why Granny Huai is able to live in this place.
An Jing nodded slightly; Granny Huai indeed had an expert behind her, otherwise it would be inexplicable how, even as a young girl back then, she could use the earth vein to prolong her life.
Moreover, her Destiny Grid was definitely quite special and held considerable value. Aside from anything else, just the fact that she could achieve a win-win situation with the earth vein made her worth cultivating.
Chapter 173