Coi Coi-Vilu or Caicai-Vilu (from Mapudungun Kaykayfilu: Kaykay a name, and filu "snake") is the god of water (or goddess, in some versions found in Chiloé) and of all that inhabits it and is who rules the seas; according to Mapuche myths (later also found in Chiloé). This snake was a central figure in the Origin Of The Chiloean Archipelago. In Mapuche mythology, Coi Coi-Vilu is son of Peripillan (a Pillan).
- Alberto Trivero (1999), Trentrenfilú, (in Spanish). Proyecto de Documentación Ñuke Mapu.
- Martinez Vilches, Oscar, Chiloe Misterioso (in Spanish). Pub. Ediciones de la Voz de Chiloe (circa 1998)