The material Liu Changxu used to refine his external incarnation was the rhizome of the Netherworld Purpleglow Lotus, which he had obtained after killing the Netherworld Sea Serpent.
Once he began refining the external incarnation, Liu Changxu discovered that the process was far more difficult than he had anticipated.
An external incarnation was essentially a replica of a cultivator's true body. Once successfully refined, it would not only share a close divine soul connection with the original but also possess the ability to act independently, placing extremely high demands on both the refining techniques and the materials.
Of course, merely producing an external incarnation did not mean the refinement was a success.
The key measure of success was how much of the original's combat strength the external incarnation possessed. Ordinarily, an incarnation with thirty percent of a Spirit Transformation cultivator's combat strength was considered adequate, while the upper limit was fifty percent of its creator's strength.
Among the external incarnations refined by Spirit Transformation cultivators, however, only a few could reach thirty percent of the original's combat strength. Those that reached fifty percent were the stuff of legend. Most possessed only ten or twenty percent of the original's strength.
An external incarnation of that caliber was only slightly stronger than an ordinary cultivator at Nascent Soul Great Perfection and could not possibly contend against an opponent of the same cultivation realm as its creator.
If Liu Changxu's external incarnation possessed only twenty percent of his strength, it would be unable to protect the lineage, making the refinement tantamount to a failure.
Although refining an external incarnation was extremely difficult, Liu Changxu still managed to give his incarnation form through his superb artifact refining skills. The next step was to split off a fragment of his primordial spirit and imprint it