If Countercurrent River were kept outside, it would be fine. But if it remained inside an immortal aperture for long, it would consume a massive amount of Heaven and Earth Qi. Once Heaven and Earth Qi became insufficient, the immortal aperture would grow unstable.
Thus, Fang Yuan had to periodically place down his immortal aperture and absorb Heaven and Earth Qi from the outside world to replenish himself.
After absorbing for a while, Fang Yuan closed the Immortal Aperture Portal.
Arriving at the bank of Countercurrent River, he was still carrying an immortal zombie body in his hand.
It was his original body.
He directly tossed the Immortal Zombie Body into Countercurrent River.
The Immortal Zombie Body immediately drifted smoothly downstream.
Using Persistence Immortal Gu and Countercurrent River, Fang Yuan continuously experimented, sending out every method he could think of in turn.
But it was useless.
"Just as expected."
"The Soul Dao Marks on the Immortal Zombie Body cannot be destroyed or suppressed with Countercurrent River. After all, they are merely Soul Dao Marks, not Immortal Gu."
"Immortal Gu from Rank 1 to Rank 8 cannot be used in Countercurrent River. But Dao Marks can still take effect. Just like before, when I had not subdued Countercurrent River, the Dao Marks on Gu Immortals could still shield and protect them. Rank 8 Gu Immortals were still the strongest in the river."
Fang Yuan analyzed continuously and found the reason for his failure.
It was impossible for him to use Countercurrent River to resolve the Soul Dao Trap on the Immortal Zombie Body.
Fang Yuan was not discouraged either. In fact, he had already made such a guess before the experiment.
He placed the Immortal Zombie Body back atop Heavenly Seal Mountain and used the Gu formation there to seal it