The Thirteen Heavens of Nine Firmaments were the source from which lightning tribulations arose.
When a lightning tribulation descended, the passageways to the Thirteen Heavens of Nine Firmaments naturally opened as well, giving cultivators the chance to enter and draw upon Innate Primordial Qi.
From Azure Firmament to Divine Firmament, the higher the level of the Nine Firmaments, the more wondrous the Innate Primordial Qi became. Above the Nine Firmaments lay Myriad Phenomena Heaven, Moon Wheel Heaven, Sun Wheel Heaven, and, at the very highest, Daluo Heaven.
If one could break through layer upon layer of tribulation lightning and charge into the highest four heavens, one could harvest the origin Qi of heaven and earth and gain even greater benefits.
Every cultivator practiced different methods and possessed different talents, so naturally their gains upon entering the Thirteen Heavens of Nine Firmaments varied as well.
Generally speaking, only by reaching the eighth level, Jade Firmament Heaven, could one possibly break through the limits of the sixth rank. Of course, this was not absolute.
Sixth-rank Pure Yang cultivators had three chances to undergo tribulation. If they accumulated enough during the latter two tribulations, they too had a chance to break through their limits. But such things had been exceedingly rare throughout the ages.
The foulness Gao Xian accumulated from killing was all absorbed by the Blood River Celestial Venerable Transformation Origin Book. The divine artifact's power had grown stronger, and the cultivation of his Taixuan Divine Image had surged as well.
Yet the accumulated foulness and Killing Intent could not truly be digested. When the lightning tribulation came, it would all erupt at once, raising the tribulation's power tenfold...
Gao Xian sought only to survive the tribulation safely. As for anything else, he truly did not dare hope for it.
Still, Bai