Lu Qing's current primary cultivation technique, the [Five Elements Body Refining Technique], is a body cultivation method.
The highest realm one can cultivate to is the Golden Core Perfection realm.
In fact, after understanding the cultivation technique left by the youth in a white robe, Lu Qing estimated that according to the classification of that youth's world, it hadn't even reached the realm of the Ninth Transition of the Golden Core.
At most, it had only achieved the Seventh Transition realm.
This is also why, in the Ancient Immortal Cultivation Era, the Golden Core realm cultivator who created the [Five Elements Body Refining Technique] ultimately couldn't achieve the Primordial Spirit.
Because he did not evolve this technique to a truly perfected state.
Lu Qing even suspected that the so-called dissolution of that Golden Core realm cultivator back then.