The buffalo-woman story belongs to a wide family of animal-bride narratives and the Yoruba version is unusually consequential for practice. Oya was a buffalo who could remove her skin and take human form; Shango discovered where she concealed it and, by holding the secret, held her. In most tellings a senior co-wife discovered the secret and taunted her with it publicly in the market. Oya returned to the hidden skin, resumed her buffalo form, and destroyed much of the town before departing, leaving her horns behind — and the horns became a means of summoning her, so that her shrine implements include them. The story accounts for several features of her cult: the association with the market where the betrayal happened, the connection with sudden and total transformation, and the presence of buffalo horns among her emblems. It is also a story about a woman whose power was contained by a secret and who took it back at cost.