The Soul Searching Technique is not a Divine Method, but it's something Su Han acquired from the memories of gods and demons. Though it has many drawbacks, its effect is quite good.
Soon, Su Han obtained a lot of information he wanted from Black Impermanence's memories.
First, the lord of Hell is indeed King Yama from King Yama's Palace.
Second, Black Impermanence hasn't heard of Ning Feifan, but King Yama does know him and is aware of Ning Feifan's relationship with Su Han. This sufficiently proves that King Yama and Ning Feifan have a very close relationship; Ning Feifan might even be in King Yama's possession.
Third, besides the lord in Hell, there's also a judge of life and death, who is a Great Saint expert with extremely great strength. Beneath the judge of life and death are the four soul-retrieving envoys: Ox Head and Horse Face, along with Black and White Impermanence.
