This was where cultivators fell short of demons. No matter how powerful their cultivation arts were—even if, like Yan Chihuo, they cultivated the Demon Race's most supreme techniques—if cultivators wished to form a Solid Core or even a True Core, they had to take superior medicinal pills. Otherwise, they could only form a Void Core.
As for the reason why, the cultivation world had yet to figure it out. At first, they believed it was a matter of bloodline. Yet some cultivators, unable to obtain the medicinal pills they needed but full of wild fancies, fused Demon Race bloodlines into themselves. The result was the same: they formed only Void Cores. Some not only failed to form an Origin Core, but turned themselves into neither human nor demon, becoming monsters condemned and hunted by both races.
Thus, no one walked that path again. Only a few scattered secret arts had been passed down for other reasons. Some cultivators also believed that demons succeeded because of their formidable bodies, and so they painstakingly researched body-refining arts. During that period, the cultivation world's body-refining arts made tremendous progress. Unfortunately, they still produced only Void Cores, though those innovative body-refining arts were passed down.
After all these twists and turns, the cultivation world had no choice but to accept reality. Although Yan Chihuo's body had been tempered by the essence blood of a great Qilin immortal from the Immortal Realm, and its strength was rare among those of the same rank, he still did not dare form a core carelessly. Given his cultivation art and the purity and profundity of his magic power, he ranked among the very best of cultivators at the same level. Even if he could not form a True Core, he had to form at least a Solid Core.