"The Fourth Essence and the Seventh essence are both very crucial ..."
Aaron sipped his tea and said reflectively, "Before becoming non-human, the path of transformation isn't hard. But if you insist on becoming a traditional 'evil spirit', it would be best if, before unlocking the Seventh Essence, you usurp and absorb the essence of 'Chi' from a powerful extraordinary being, and follow a new path ..."
"Why?" Lilliatte looked baffled.
"Opening the door to immortality is a dangerous task, and it also needs a choice …... The ones in charge of this path, Si Sui and hidden existences, have a much stronger control over the route than you'd imagine."
Aaron suggested meaningfully: "If you do not want to be controlled by them after you promote yourself to 'immortal', it's best to prepare in advance! Well …these are extremely precious top-secret knowledge, which I only obtained from the Cult after I ascended to non-humanhood. Remember, don't reveal it to others!"