The Element Encyclopedia of Witchcraft: The Complete A-Z for the Entire Magical World - Judika Illes 2005
The Horned One and The Devil
Aatxe, the name of this Basque deity, means “young bull.” Another name for him, Aatxegorri, means “young red bull.” Another Basque spirit named Etsai may or may not be identical with Aatxe. It is unclear whether there were originally two distinct spirits or whether Aatxe, having come to the attention of the Inquisition during their search for Basque witches, evolved into Etsai, a spelling more amenable to French and Spanish clerics.
Aatxe is a shape-shifter who can assume human form but most frequently manifests, as his name indicates, as a bull. (Other forms include dragon, goat, horse, and pig.) Like the Minotaur, Aatxe lives deep within Earth but reputedly leaves his cavern home on stormy nights (with the implication that Aatxe is responsible for the storms). Aatxe is among the spirits affiliated with the goddess Mari. Some believe that Aatxe is really among Mari’s many manifestations.
Etsai is frequently described as an “evil spirit,” although whether he has always been “evil” and dangerous or whether this reputation stems solely from Christian perceptions is now unknown. The name “Etsai” has become synonymous with “devil.” Etsai allegedly teaches his devotees arts described by Christian sources as “diabolical.” His classroom is a mountain cave. Allegedly, even his students fear him because he always forces one student to remain permanently with him following graduation, although exactly what happens to them when they stay is unclear. The intended implication is that staying with Etsai is similar to being trapped in Hell.
See also Akerbeltz, Devil, Minotaur; DIVINE WITCH: Mari.