S1·E30 Episode 30

Su Yi Shui succeeds in sealing the Spirit Spring in the netherworld, along with the drop from his heart, but the fallen immortal Ye Xin (the uncle who raised the Mu sisters) puts a curse on him. This causes him to lose memory of the last 20 years of his life. Ye Xin proves to be Dun Tian, the founder of the Eternal Sect. Regretting that he has sacrificed his family in order to ascend, he wants to start anew and, for this purpose, joins hands with Prince Su Yu. Su Yi Shui becomes a totally different person: arrogant, extravagant, not recognizing his disciples and treating them poorly, stuck back at the moment he wanted to kill Mu Qing Ge.