The Sky primitively in Basque mythology, he became later an equivalent of Heaven. During the evangelisation of the Basque country, it was thus nearly natural that the Christian God might be related to Ostri, and thus named. This being is often represented by the "lauburu" (literally, "four heads", it is a sort of swastika), that symbolises the contrasted forces of good and evil (depending on which direction the wheel of the swastika turns). Other designations are Ost, Ortz, Ortzi, Ortze, Urci and Urtzi. Its name is also the base for the appellation of other minor deities or spirits.