Picked this up in a small and inexpensive lot, all from Pergamon.
Pergamon, Mysia, under alliance with the Roman Republic
200-30 BC
AE 14 (Chalkous?)
Obv: Bearded bust of Asclepius, God of Medicine
Rev: Rod of Asclepius with snake, AΣKΛHΠIOY ΣΩTHΡOΣ (Asclepius the Savior)

In Greek mythology, Asclepius was the demigod son of Apollo and a mortal woman named Coronis. She died while pregnant, and the baby Asclepius was saved via Caesarean section by Apollo before the mother was cremated. The baby Asclepius was given by Apollo to the centaurs, who raised and educated him. He was granted knowledge of healing by a serpent, who remained with him, wrapped around his staff. Various heroic deeds are attributed to Asclepius in myth (often contradictory to one another) but all sources agree that the mortal Asclepius was slain by Zeus, either out of fear of his ability to make humans effectively immortal, or following protests from Hades, whose underworld was being emptied when Asclepius unlocked the secrets of resurrection. Asclepius was later deified, his temples doubling as hospitals where the sick would come for healing. It is said that snakes were allowed to roam freely within his temples.
Pergamon in Mysia was the site of a prominent temple to this god, who often features prominently on its coinage.
The lot contained a few more of this same type, but curiously the bust on this coin is much smaller than the rest--I wonder if this could be a muled die pair from a smaller denomination?