In Taoism, Niu Tou Mahai are the demons of the underworld. They are the grassroots executors under the command of high-level Yin deities such as Dong Yue Dadi， Feng Du Dadi， and the Ten Dwarfs’ Court of Justice.
Physical characteristics： Niu Tou Mahai have the body of a human and the head of an ox. They have horns on their heads and have a terrifying appearance. Sometimes they are called Abang or Abfang. Mahai， on the other hand， have the head of a horse and a human body. They have a long face and big eyes. Their appearance is also fierce. Both usually hold tools of punishment such as steel forks， iron chains， or shackles.
Functions and duties： Their main responsibility is to follow the orders of the Ghost King or the records in the Book of Life and Death to go to the human world to lock and take the deceased souls who have died or should die to the underworld. They lead the deceased souls through the Yellow River Road， cross the Yehan Bridge， and guard the gates and prisons of hell. They also assist other demons in the hell to inflict various cruel punishments on the sinners.
Cultural integration： The concept of Niu Tou Mahai originated from Buddhism， and there are descriptions of “Niu Tou Abang” (ox-head demons) in ancient Indian mythology and Buddhist scriptures. After Buddhism was introduced to China， it merged with the local concept of “Taishan Controls Demons” in China， the Taoist “Lu Feng Shan” hell system， and folk legends. Around the Tang and Song dynasties， with the popularity of popular storytelling， vernacular tales， and folk stories， Niu Tou and Mahai began to appear as a fixed pair and integrated into the Taoist system of the afterlife.
Popular image： In folk stories and literary works， Niu Tou Mahai are sometimes portrayed as characters with “human-like” characteristics. Although they fulfill their duties faithfully， their families of the deceased will bribe them with paper money and offerings. They are fierce towards ordinary deceased souls and are helpless when encountering ghosts with backgrounds or particularly fierce personalities.
