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Psychedelic trance or psytrance is a form of electronic music characterized by hypnotic arrangements of synthetic rhythms and complex layered melodies created by high tempo riffs. It first broke out into the mainstream in 1995 as the UK music press began to report on the trend of Goa trance. Since then the genre has grown immensely and now offers much variety in terms of mood, tempo, and style. Some examples include full on, dark, progressive, suomi, psybreaks and psybient.