Nguruvilu

The Nguruvilu Is a mythical creature originating from the Mapuche religion of the indigenous peoples of Chile. Residing in rivers, this creature appears to have the head and forelegs of a fox while having a long, serpentine body. Sinister and sneaky, nguruvilus are known to kill humans attempting to cross the rivers they inhabit. They make the river appear shallow enough to cross on foot, but then create deadly whirlpools to trap and drown hapless victims. A nguruvilu can be vanquished by a kalku (sorcerer) or machi (shaman). They do this by diving into the whirlpool where the nguruvilu resides and using magic to capture it. The sorcerer then threatens the nguruvilu with violent mutilation unless the creature makes the river safe to cross. After the nguruvilu has done so, it is released. It is of great importance that everyone living by the river witness the creature's capture so that they do not fear crossing the river. The kalku is then rewarded for their service with gifts and offerings.

As for the thwarted nguruvilu, it will travel further down the river to the next nearest popular crossing point in order to torment those that live nearby.