Lin Fan and a saintess simultaneously transmigrate to different worlds, only to discover they can switch bodies with each other infinitely. Subsequently, the two clash in different time periods. One day, Lin Fan returns from a transmigration, only to find that he has become a Xian! Suddenly becoming a Xian, what does he do? Online waiting, quite urgent. (PS: Also known as, "I've Got a Substitute Player," "My Saintess's Scientific Cultivation," etc., please feel free to collect it)