The depiction of the Qi Restraining Stage had, in fact, already been mentioned within Earth's martial cultivation theories.0

In traditional martial arts, Qi Restraining was defined as the ability to close the body’s pores and lock in its inner heat and energy. This ensured that the results of cultivation would not easily dissipate, thereby preserving the body's vitality and blood energy.0

In some high-martial realms, however, the definition of Qi Restraining went further. It was seen as the perfect and skillful control over one's true qi, allowing the qi to circulate internally in a profound and mysterious manner without leaking out. This meant that an opponent could not judge one’s cultivation level or combat strength based on aura or pressure.0

As for the Four Extremes Realm, its interpretation of the Qi Restraining Realm, specifically in regard to the extreme of ‘Essence,’...0