Medusa

Medusas (often called gorgons on Theros) are closely associated with Pharika, the god of poison and Medicine. Pharika has charged her Favored servants with guarding Secrets of life, health, and immortality that are too powerful to be known by those who lack the Wisdom to use them properly. Those who approach a Medusa with humility and worthy offerings might receive the creature's favor. The Medusa might propose a dangerous quest to fetch some rare ingredient or legendary relic, promising to reward success with a bit of Pharika's knowledge. This information might lead to a cure for a plague, an alchemical breakthrough, or a Secret of the cosmos.
As deadly as they are ravishing, the serpent-haired medusas suffer an immortal curse brought on by their vanity. They lurk in quiet exile among the tumbled ruins of their former lives, surrounded by the Petrified remains of past admirers and would-be heroes.
Men and women who desire eternal youth, beauty, and adoration might pray to malicious gods, beg Dragons for ancient magic, or seek out powerful archmages to fulfill their wishes. Others make sacrifices to demon lords or Archdevils, offering all in exchange for this gift, oblivious to the curse that accompanies it. Those who strike such bargains gain physical beauty, restored youth, immortality, and the adoration of all who behold them, granting them the Influence and power they so desire. However, after years of the living like a demigod among mortals, the price for their vanity and hubris is exacted, and they are forever transformed into medusas. A medusa’s hair turns into a nest of venomous serpents, and all who gaze upon the Medusa are Petrified, becoming stone monuments to its corruption.
Medusas live forever in seclusion, alienated from the world around them by their monstrous form and caprice. Their homes gradually fall into disrepair until they are little more than shadowy ruins covered with thorns and creepers, riddled with obstructions and Hiding places. Foolhardy looters and Adventurers who enter are often unaware of the medusa’s presence until the creature is among them.
A Medusa is subject to its own curse. By looking vainly on its reflection, it turns to stone as surely as any living mortal. As a result, a Medusa destroys or removes any mirrors or reflective surfaces in its lair.