The flask like item that Y uses on the fading Quin Shayak (original Quin) is the same item that Wang Yi used in chapter 118-119 on the original protagonist on the cultivation world that allows a soul to reincarnate. Or more accurately it guarantees a reincarnation, but it may occur in a different novel world.
Spoiler for latest chapter (172):
The flask like item that Y uses on the fading Quin Shayak (original Quin) is the same item that Wang Yi used in chapter 118-119 on the original protagonist on the cultivation world that allows a soul to reincarnate. Or more accurately it guarantees a reincarnation, but it may occur in a different novel world.