In the Desolate Era world, the mainstream paths of cultivation included Qi Refining, Body Refinement, and Heartforce, three entirely distinct systems.
Of these, the prevailing Heartforce cultivation system was incredibly crude. Most chaos worlds, and even Eternal Regions, lacked any systematic guidance for it. It was mainstream only in a tiny handful of worlds.
The path of Divine Demon Body Refinement had been created by cultivators studying naturally born divine demons. Since divine demons existed so widely, this path was relatively mature in both backward native worlds and the clusters of chaos worlds controlled by Dao Lords.
By contrast, Qi Refining was a path developed by cultivators themselves. Their differing early circumstances had led to enormous disparities between their methods.
In a native chaos world like the Three Realms, which had never produced a Chaos Immortal, Qi Refining methods were extremely crude. Even those who painstakingly transformed themselves and became Celestial Immortals were merely the weakest, third-rank Celestial Immortals, utterly incomparable to Heavenly Gods of the equivalent stage on the Divine Demon Body Refinement path.
Worlds with Chaos Immortals, however, often possessed more developed Qi Refining methods that could help cultivators form second-rank and first-rank Celestial Immortal Golden Cores.
Second-rank Celestial Immortal Golden Cores required certain exceptionally precious external resources to establish their foundations. Their magic power already far surpassed that of third-rank cores in both quality and quantity. Though they still struggled to match Heavenly Gods at the same stage, the difference was not great.
First-rank Celestial Immortal Golden Cores required the assistance of a powerful existence on the level of a Chaos Immortal. Only by gathering the strength of an entire major world or absorbing enormous quantities of chaos energy could one condense a golden core of the highest rank.
With such a golden core, a First-Rank Celestial