The demigod Pan was the patron of shephards and being 'half goat' was associated with wild nature. Usually he is found in association with Dionysus ie Bacchus. The 'orgiastic' worship of Dionysus involved rituals and intoxication leaving the revelers in a state of frenzy in which wild animals were often ripped apart and eaten on site. Originally a 'female' cult it was endemic in Greece eventually spreading to Rome where it was later banned outright.
from wiki
Livy, reporting the evidence given by a woman who had been involved in the rites to a Roman investigative consul, writes:
"there was no crime, no deed of shame, wanting. More uncleanness was committed by men with men than with women. Whoever would not submit to defilement, or shrank from violating others, was sacrificed as a victim. To regard nothing as impious or criminal was the sum total of their religion. The men, as though seized with madness and with frenzied distortions of their bodies, shrieked out prophecies; the matrons, dressed as Bacchae, their hair disheveled, rushed down to the Tiber River with burning torches, plunged them into the water, and drew them out again, the flame undiminished because they were made of sulfur mixed with lime. Men were fastened to a machine and hurried off to hidden caves, and they were said to have been taken away by the gods. These were the men who refused to join their conspiracy or take part in their crimes or submit to their pollution"
Euripides wrote a Drama "The Bacchae" in which King Pentheus out of curiousity secretly goes to spy on the female rituals. He is spotted by the women and chased down as an "animal" and ripped to pieces by a mob of women which includes his own mother. When the Triumvir Crassus was defeated and killed by the Parthians at Carrhae his head was brought to the Parthian King Orodes who was said to be watching a 'production' of the Euripides tragedy. The head of Crassus is said to have been used as a prop.
Dionysus worship was not restricted to such wild ecstatic 'festivals'
The annual Spring Tragedy performances which premiered the works of Euripides Sophocles and the 'great' father of drama Aeschylus were in honor of Dionysus. As described by my Drama professor so very long ago. Although usually associated with drunkeness Dionysus was also the God of the 'first' glass of wine where inspiration and artistic endeavors are often formulated.