Whether Human Race martial cultivators or eternal Giant Spirits, their cultivation of the Heavenly Rules and Dao Laws generally fell into five stages: Modeling Oneself on Heaven and Earth, Celestial Person in Harmony with the Laws, Celestial Person Unity, True Union with the Dao, and the Gate of Creation.
"Modeling Oneself on Heaven and Earth" meant studying the experience left by predecessors, or observing the various phenomena of heaven and earth, then deducing complete Heavenly Rules and Dao Laws and incorporating them into one's Martial Dao.
The next stage, "Celestial Person in Harmony with the Laws," meant merging oneself into a Heavenly Rule and Dao Law, uniting person and Dao to draw greater power from that Heavenly Rule-one of the necessary conditions for mortals to break the Limit Between Humans and Gods and enter the Transcendent Rank.
"Celestial Person Unity," also called "God and Dao as One," was the process of further merging with the Heavenly Rules and Dao Laws, fusing one's Primordial Spirit with a Heavenly Rule. At this stage, their fortunes were bound together. Those who achieved Celestial Person Unity, God and Dao as One, could almost all become the True Spirit of a Heavenly Rule.
This was also the key to Illuminating Eternity and becoming an Eternity God.
In reality, however, many Eternity Giant Gods could not accomplish this. Their Heavenly Order Power did not reach this level.
But their bodies were naturally powerful, and most relied on their flesh and blood alone to directly achieve Illuminating Eternity and gain endless lifespans.
After Celestial Person Unity came "True Union with the Dao": truly joining with one's Heavenly Rules and Dao Laws and taking complete control of them. Those who achieved True Union with the Dao could generally possess the power of Middle Eternity or even Upper Eternity