The Mapuche people of Chile have a rich folklore that is reflected in their religion. Within its pantheon is an immortal, godlike, vampiric leviathan named Cai Cai Filu. Its natural form is that of a tsunami or tidal wave, but it can shapeshift into an ox and a horse. Living on the bottom of the ocean, it is constantly, ravenously hungry for human flesh and blood. Regular sacrificial offerings made to this monster can stave off its attack — a tidal wave crashing down upon the Mapuche.

Cai Cai Filu is one of the old gods, worshipped before the introduction of Christianity. After the Mapuche began to meld this new religion with their traditional one, changes had to be made. Cai Cai Filu was made into a demon by early missionaries and was described as a consumer of sinners.

Source: Benjamins, Death of 4 European Gods, 19; Maccoby, A Pariah People, 192; Tierney, The Highest Alter, 132