In the Xuan Yu Realm, Immortal Profound Crystals were the lifeline of those in the Immortal Realm.
When injured in battle, one needed Immortal Profound Crystals to recover. When one's power was exhausted, one needed Immortal Profound Crystals to replenish it. Even the use of certain powerful secret arts required burning Immortal Profound Crystals as the price.
Flint Fire Nirvana could restore oneself in critical moments in place of Immortal Profound Crystals, effectively saving a portion of them and indirectly increasing one's endurance and margin for error.
Especially in protracted battles or wars of attrition, it could continue accumulating power in preparation for the next recovery. This characteristic was quite valuable.
However, this characteristic could not improve combat power. It was not bad, merely different from what Chen Fei wanted.
Chen Fei arrived before the third sphere of light and reached inside. A completely different torrent of information surged into his Sea of Consciousness.
Ember Tracing Cause
After the Chaos Furnace successfully devoured a complete opponent's origin, it could use chaos flames as the guide to conduct a deeper "retrospective burning" upon that devoured origin.
During this retrospective burning, several of the target origin's most deeply imprinted and core memories or karmic fragments from before death would be forcibly stripped away and revealed, as clear as pages turned open in a book.
The depth of the tracing and the amount of information obtainable depended on the completeness of the devoured origin and the target's cultivation realm while alive.
A trace of surprise flashed through Chen Fei's eyes.
"Devouring the core origin... This was clearly a form of forced, deeper 'soul searching' performed upon an opponent's remaining origin after killing them!"
Chen Fei immediately understood the essence of Ember Tracing Cause.
Ordinary soul-searching arts had extremely limited effects even against Immortal