A legend describes a Navarrese knight, Teodosio de Goñi, who while making penance for double parricide in the Aralar Range rescues a woman that had been given as ransom to the dragon.
When the chains that tie his ankles are bitten by the dragon and he sees no way of defeating it, the knight prays to Saint Michael to save him.
In Heaven, the archangel is notified, but refuses to enter the fight without God.
The archangel arrives with God over his head and decapitates the dragon, liberating Teodosio from his chains and ending his penance.
It has been interpreted as a way of justifying the break from the religion and customs of pagan Basques and the adoption of Christianity and, specifically, the veneration for St. Michael.