At the top of the Black Heavenly Treasure Tree, Lin Feng sat. His body and mind were in their perfect condition.
"Let us begin," Lin Feng closed his eyes and with his mind's eye, he viewed his body. A white jade aurous core brimmed with a spinning purple light.
Under Lin Feng's control, the mana in his body began to work.
A thick torrent of mana swept through Lin Feng's body like water after a dam had been breached.
Following which, the mana went 'boom' and began to burn like matchsticks that had been lit. The mana burned from feet-first all the way to the top of Lin Feng's head. Evidently, it was Immolation by the Yin Fire.
This was the Tribulation of the Yin Fire!
As one progressed the middle stage of the Aurous Core stage, one must go through the Immolation by the Yin Fire. Successfully going through this stage would bestow one with unlimited chances for progression and advancement. Failure to do so would reduce one to ashes.