"As you are aware, I know little about the martial path, but I understand how the immortal path of qi cultivation works." Upon hearing An Jing's inquiry, Yvelbane answered with confidence. "As qi cultivation prevails in this world, I shall clarify a few points for you."

The sword soul had grown more open and forthright through their shared experiences. "The immortal path of qi cultivation begins with qi essence. Qi essence is aura. It's the innate qi of the human body, a pure and true energy synthesized by the union of yin and yang, emerging when the soul and flesh become one.

"Physical conditioning serves only to build vigor. By practicing contemplation techniques, combining physical movement with breathing exercises, balancing internal and external techniques, and using spirit incense to enter meditation, one achieves unity of body and soul that kindles the first wisp of innate qi.

"But nothing is fixed. Yin and yang, stillness and motion, constantly flow into each other. As the saying goes, all thousand methods lead back to the Grand Dao. In this regard, the martial path and immortal path are essentially one and the same—Silk, River, and Tide. However, the paths diverge thereafter."

Yvelbane continued slowly, "Spirit roots are the physical embodiment of one's natural gifts. Without one, the transformation of vigor and essence is all but impossible, as is the absorption of spirit qi in the environment for further refinement.

"Even those born with spirit roots must nurture their innate qi to fully restore it. This expansion, achieved through the refinement of qi essence, constitutes the foundational stage of qi cultivation, that is, the Spirit Awakening Realm.

"Upon reaching the peak of the Tide Essence Stage of the Spirit Awakening Realm, the purple mansion and spirit roots are nourished by qi essence and grow ever more robust. The purple mansion brings forth spirit sense and enables the absorption of spirit qi from the environment, which is then refined into spirit energy through the spirit roots, feeding back to nourish the physical form. This initiates a profound metamorphosis from mortal flesh toward an immortal foundation.

"This is the next step on the immortal path of qi cultivation, that is, the Qi Refinement Realm. At this point, a cultivator gains an additional 60 years of life, pushing their lifespan to a total of 180 years.

"Beyond the threshold of the Qi Refinement Realm lies the Foundation Building Realm. When spirit qi has tempered the flesh to its absolute pinnacle, the purple mansion nurtures the soul. This shatters the natural barriers, allowing one to absorb the pure essence of heaven and earth and condense their qi essence and spirit energy within the body into their natural counterparts, profound essence and various profound qi.

"Profound essence originates from the Dao, or the Source. A common example is the cultivation of sun purple qi and moon radiance through solar and lunar immersion. The various profound qi are the primal, chaotic energies inherent in all things. They fall into three categories: heavenly, earthly, and human lethal qi, with the latter two being more common. Prime examples include subterranean flame-lethal qi and war blood-lethal qi.

"Together, they combine to form universal innate qi, or spirit qi. Cultivators use profound essence and profound qi to completely transform their physique and foundation. From this point forward, their qi essence is directly converted into their chosen profound qi. This complete metamorphosis pushes one across the threshold into the immortal realm and extends their lifespan to 360 years.

"However, this also means that once cultivators reach the Foundation Building Realm, they are bound to techniques that align with their chosen profound qi. Because there's no room for change, this realm is known as the 'gateway of no regrets' and the 'foundation of no return'.

"As the 'three hurdles to the dao foundation,' the three realms, which fall within the mortal domain, are the ultimate obstacles to building one's dao foundation. Take but one more step, and you will shed your mortal coil to ascend into the immortal ranks."

Yvelbane explained in a clear and articulate manner, "Although Evenstar Ivory Divine Seal requires nurturing qi essence to grow, you can begin refining qi in advance. By merging mystic-metal lethal qi with your own qi essence, you refine Evenstar lethal qi, granting you the strength of a Qi Refinement cultivator ahead of time.

"But you must be meticulous when selecting mystic metals. The purer the metals, the more refined your Evenstar lethal qi becomes. Only then can you bear the most potent types of profound qi and forge an unrivaled dao foundation."

An Jing lapsed into a pensive silence, weighing the weight of the sword soul's words. "I see."

Etching these principles into his mind, An Jing swallowed the final morsel of meat and said, "Evenstar Ivory Divine Seal condenses seals by refining lethal qi, but the body can't generate lethal qi on its own until an immortal foundation is established.

"Before that breakthrough, a cultivator must extract lethal qi from mystic metals, hence its other name: Evenstar Metal-Devourer. Just as you said, this was how ancient sword immortals tempered their flesh upon achieving a certain level of cultivation."

It was clear this technique was intended for seasoned Foundation sword cultivators, allowing them to fuel their progress with their own lethal qi. After all, how could a mere Qi Refinement novice hope to afford the mountain of mystic metals required for such an extravagant path?

"Indeed." Observing An Jing's keen discernment, Yvelbane said with a hint of appreciation. "Body refinement and the path of a martial cultivator share commonalities. In light of these changing times, I chose Evenstar Ivory Divine Seal as it's a technique that remains viable across all realms, so long as mystic metals are within reach. Even if your progress stalls, you won't lose the physical tempering you've achieved. Should you shift toward the martial path, your efforts won't be in vain."

Yvelbane was indeed wholehearted in its instruction. Only a true mentor would show such meticulous care, planning for every circumstance.

An Jing wouldn't sacrifice his cultivation just because he was backed into a corner and desperately needed firearms to survive the crisis. Even now, he was perched on the sofa in the back room, locked in meditation and completely tuned out from his surroundings. With every measured breath, he regulated his aura. His vigor surged as his body radiated waves of heat like a white-hot furnace.

Midway through his own recovery, Huo Qing snapped out of his meditative state to stare at An Jing in surprise. Torn between interrupting An Jing and the fear that something was going wrong, he called Metalhand over to check on him.

Metalhand's impatience vanished the moment he saw An Jing, replaced by a pensive expression. "A top-tier vital cultivation technique... The kid has got to be a prodigy from some great tribe out in the badlands!"

But for some reason, he's here in the Mortality Plains all alone. Don't tell me... this has something to do with Big Brother and the others...

Shaking his head, Metalhand urged Huo Qing to let An Jing be. After some thought, he set up a mini wood spirit formation to gather vitality.

"Consider it a free gift," he muttered, "Make sure you come and find me if your tribe has any big business proposals later on."

An Jing sensed the surge of spirit qi and his furrowed brow relaxed. Soon, a day slipped by in his meditative state. The vitality from the wood spirit formation and the nourishment from the canned meat revitalized An Jing, stripping away his fatigue and healing old injuries.

As he woke, a flash of dark crimson flickered in his eyes. An Jing exhaled a long, sharp breath that struck the ground like an arrow, ringing out with a metallic clang.

"You're awake?" Metalhand called out at the sound of the commotion in the rear building. "Now that you're up, get over here. I've restored the OverSight sword case for you."