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Ox-Head (simplified Chinese: 牛头; traditional Chinese: 牛頭; pinyin: Niútóu; Wade–Giles: niu2-t'ou2) and Horse-Face (simplified Chinese: 马面; traditional Chinese: 馬面; pinyin: Mǎmiàn; Wade–Giles: ma3-mien4) are two guardians or types of guardians of the underworld in Chinese mythology. As indicated by their names, both have the bodies of men, but Ox-Head has the head of an ox while Horse-Face has the face of a horse. They are the first beings a dead soul encounters upon entering the underworld; in many stories they directly escort the newly dead to the underworld.[1]
In their duties as guardians of Diyu, the realm of the dead, their role is to capture human souls who have reached the end of their earthly existence and bring them before the courts of Hell. Souls are then rewarded or punished based on the actions performed in their lifetime.
Ox-Head and Horse-Face also play the role of messengers of the king of hell, Yanluo Wang (閻羅王). In one legend, Ox-Head was created by the king when he took pity on a recently deceased ox who had worked hard all his life, so the king made him one of his faithful servants.[2]
In the Chinese classical novel Journey to the West, Ox-Head and Horse-Face are among the underworld denizens overpowered by Sun Wukong after his soul is dragged to hell in his sleep. He then crosses out his name and those of all non-human primates on earth from the record of living souls, hence granting a second level of immortality to himself and general immortality to his monkey children.
In Japanese mythology, Ox-Head and Horse-Face are known as "Gozu" and "Mezu" respectively. They appear in classical Japanese literature such as the Konjaku Monogatarishū and Taiheiki. In The Tale of the Heike, they appear in an ominous dream of Taira no Tokiko.
In Vietnamese mythology, the Ox-Head and Horse-Face are called Đầu Trâu and Mặt Ngựa or Ngưu Đầu and Mã Diện. They are also responsible for leading people's souls to the underworld after death.