Outside Absolute Yin Valley, Gu Yi ran through the cultivation essentials of the Profound Yin Art in his mind.
The Profound Yin Art was a peculiar martial skill. It began as a mortal-grade martial skill, but in places where the yin energy of heaven and earth was dense, it could continuously devour yin energy as though there were no end to it, constantly evolving.
To begin cultivating this martial skill, one needed to draw upon the yin energy of heaven and earth and form yin-energy vortices around the three acupoints in the chest: the Heavenly Palace Acupoint, Divine Palace Acupoint, and Yin Capital Acupoint.
Once the yin-energy vortices formed, they could actively devour the surrounding yin energy of heaven and earth.
When the yin energy accumulated to a certain degree, three Yin Pearls would form at the centers of the three vortices and sink into the three major acupoints.
But that was not the end. The yin-energy vortices could continue absorbing the yin energy of heaven and earth and condense more Yin Pearls.
As the number of Yin Pearls within the acupoints increased, the greater the power the Profound Yin Art could unleash.
With Gu Yi's current cultivation, cultivating the Profound Yin Art was extremely fast.
In just a few breaths, Gu Yi absorbed the surrounding yin energy of heaven and earth, condensing vortices at the three acupoints that spun at an astonishing speed.
The moment the tiny vortices formed, they erupted with a powerful suction force.
The yin energy of heaven and earth that had lingered in the Absolute Yin Flatland for countless years seemed to find an outlet at once. It gathered frantically from every direction and poured into Gu Yi's body.
The moment the yin energy of heaven and earth entered the vortices, it was immediately refined