Tradition: Brazilian Mythology
Alternative names: Onça-Boi
Category: Cat, Cow
The Myth
The Onça-Boi is a creature of Amazonian folklore whose existence is said to have been reported by fishermen, hunters, and bushmen travelling through the forests.
The creature resembles a jaguar, but possesses the physical characteristics of cattle: hooves and horns.
Unlike ordinary jaguars, which generally hunt alone, Onças-Bois are said to always hunt in pairs. The two creatures work together to corner their prey, which is primarily made up of hunters who encounter them in the wilderness.
When pursued by a pair of Onças-Bois, a hunter’s best immediate chance of survival is to climb a tree. However, the creatures are patient hunters. They take turns watching their trapped victim, waiting beneath the tree until exhaustion, hunger, or sleep causes the hunter to fall.
According to the legend, there is only one reliable way to survive an encounter with a hungry pair: kill one of the Onças-Bois.
Once one of the creatures is killed, the surviving Onça-Boi immediately flees, abandoning the hunt.
Sources
“Onça-Boi.” Mythus Wiki. Fandom. Accessed August 29, 2026. https://mythus.fandom.com/wiki/On%C3%A7a-Boi