One batch of Medicinal Material Essence after another gradually began to merge.
Xiao Yang was extremely cautious throughout the refining process.
Unlike before, he did not fuse all the Medicinal Material Essence in one go.
After all, this was his first time refining a Ninth-grade Profound Pill.
Before merging each portion of Medicinal Material Essence, Xiao Yang used his Soul Power again to sense its medicinal properties and medicinal potency.
Only after confirming that the medicinal potency was suitable did he merge it with the other Medicinal Material Essence.
With the help of the Origin Fire, batch after batch of Medicinal Material Essence fused together perfectly.
Gradually, under Xiao Yang's control, the surrounding energy also began to continuously merge into the Medicinal Material Essence.
Why were Ninth-grade Pills so difficult to refine?
It was because not only did one's alchemy ability need to be formidable, but one's control over Heaven and Earth Energy also had to reach an exceptionally precise level.
Ninth-grade Pills required more than just the fusion of medicinal materials; they also required the fusion of vast amounts of surrounding Heaven and Earth Energy.
This was also why Ninth-grade Pills had such demanding environmental requirements.
Ninth-grade Treasure Pills were somewhat better, but the energy required for Ninth-grade Profound Pills was enormous.
If he had not been inside the Exotic Fire Tower, where Xiao Yang could control the tower's energy and continuously gather it here,
then in the outside world, he might have needed to draw upon the Heaven and Earth Energy within a hundred-mile radius!
If a pill at the level of a Ninth-grade Profound Pill failed during refinement, it would also cause a loss to heaven and earth.
Once a Ninth-grade Profound Pill was successfully refined, Pill Rain would descend and nourish heaven and earth in return.