Cultivators in Mount Shu generally had to use their primordial spirit as the foundation to cultivate a Nascent Soul. A newborn Nascent Soul was truly as tender and fragile as an infant; if it strayed too far from the body, it could easily lose its way back. Only through continued cultivation could that infant gradually mature, until at last it could undergo Ascension to the Lingkong Immortal Realm and become a heavenly immortal, as Lu Rongbo had.
If one could ascend together with one's physical body, one could become a Golden Immortal, as Elder Longbrow had.
If one lost the physical body before forming a Nascent Soul, leaving only the divine soul, and continued cultivating in that state rather than entering a new body through reincarnation, one became a Ghost immortal, as Yuan Hua had.
If one formed a Nascent Soul but could not undergo Ascension for one reason or another, remaining forever on earth yet enjoying an unlimited lifespan and never dying, one was an earth immortal.
These were the stages of cultivation, and one's level of Dao Practice was reflected entirely in them. The strength of one's magical power had no direct relation to this. Perfected Red Staff, for instance, had entered the Dao during the Tang Dynasty and remained an earth immortal without ever undergoing Ascension, yet his magical power had essentially reached the level of a Golden Immortal. His disciples had not undergone Ascension either and were still earth immortals, but their magical power was already at the level of heavenly immortals.
Another example was Old Man Withered Bamboo of the Two Elders of Great Wilderness. Though he was an earth immortal, even the Azure Emperor's son, who had been banished from the Immortal Realm and cast down into the mortal world, had failed despite repeatedly