Lingfeng mountain is a location that appears in the Legend of Luo Xiaohei webseries, its manhua adaptation and in the credits of the Legend of Hei movie.
It's where Fenmo, Huniu, Qiguo and Muluo live. It's a lush mountain full of spirits and fairies. A-Gen and Luo Xiaohei visit it once[1] to help Qiguo when his body was possesed by Muluo. Muluo has since apologized for that[2].