After an unknown amount of time, the spiritual energy around them grew turbid, and dense Earth Qi began to permeate the air.
As they continued deeper, the mist thickened and gradually turned into heavy Yellow Qi. In the end, wisps of Mysterious Yellow Qi even appeared.
As everyone knew, Mysterious Yellow Qi was purer than Yellow Qi.
It was a heavenly treasure for body refinement and could strengthen the physical body.
When used to forge magical artifacts or treasures, it could even amplify their power.
Even so, Nü Tu and Xu Qiansui did not stop, continuing onward into the depths.
After descending for a long while, the surroundings suddenly opened up. The previous narrow twists and turns were gone, and all light vanished completely, plunging them into utter darkness.
A faint yellow spiritual radiance emanated from Nü Tu's body, illuminating a small area before her.
At the same time, the Earth Qi grew increasingly dense, nearly condensing into something tangible.
The pressure around them mounted, like an invisible mountain bearing down heavily upon the two of them.
Nü Tu circulated her mana, while Xu Qiansui activated his Spirit Runes, resisting the invisible pressure around them.
Deep within the Earth Vein, the gentle warmth of a Spirit Vein had long since vanished. Only dense Mysterious Yellow Qi rolled and flowed through the air.
It felt sluggish to the touch, and even a single breath made it seem as though a heavy, congealed force had wrapped around one's organs.
Aside from the Mysterious Yellow Qi so dense it could not disperse, the stone walls were covered in ancient, obscure patterns. A dim golden gleam flickered over them, with faint spiritual energy fluctuations between the lines.
They seemed naturally formed, yet also seemed carved by human hands.
Though weathered by countless years, they