"Battlefield Number Twenty-One encompasses the three-hundred-million-li Crimson Flame Mountain Range... The Crimson Flame Stone produced there can be refined into crimson flame crystals, which are immensely useful both for replenishing the fire of the Five Elements and for cultivating fire-element Immortal Arts and the Destruction Immortal Art..."
After a Celestial Immortal established a Grotto-Heaven, the next step was to complete its Five Elements qi. Once all Five Elements were present, they would drive the Grotto-Heaven's evolution into a world. Once formed, that world possessed Yin-Yang and the Five Elements, creation and destruction. Not only could it accommodate living things, its structural stability also exceeded a Grotto-Heaven's by more than tenfold. Most importantly, it allowed a Mysterious Immortal to continuously generate immortal power as though from nothing.
If becoming a Celestial Immortal greatly increased one's immortal power capacity, becoming a Mysterious Immortal brought defense and immortal power recovery close to their limits.
Given that crimson flame crystals helped complete the fire element of the Five Elements, their value was easy to imagine.
"The Dao Realm has the stage of Five Qi Returning to the Origin, which tempers the body's five viscera. A Celestial Immortal completing a Grotto-Heaven's Five Elements... is tantamount to tempering an entire Grotto-Heaven as one's own body."
Li Xian pondered this.
But on closer consideration, that was indeed the case.
For a Celestial Immortal, the Grotto-Heaven was the true body. The immortal body...
Was merely the Grotto-Heaven's guardian.
Even if destroyed, it could quickly be reconstituted.
Of course, reconstituting an immortal body after its complete destruction still took time. During that interval, the Grotto-Heaven was effectively defenseless, and its structure, only just delineated by Yin-Yang, was easily destroyed.
Thus, if destroying one's immortal body still failed to force the opponent back or gravely wound them, it essentially meant