Tale of the Nine-Tailed 1938 Episode 10

In the painting at Bando Hotel, Room 404, the three mountain gods face Ushiuchibo. At the snap of his finger, Hong Joo and Moo Yeong vomit blood. Lee Yeon is searching for an antidote in the woods when he encounters an injured old man. The old man turns out to be Onyudo, a mercenary. As black smoke emerges from his mouth, something unbelievable happens. They switch bodies! (Source: Prime Video)