Although Medusae are relatively rare, even the earliest Tibian historians have mentioned them in their writings. There has been much speculation as to what exactly Medusae actually are and several theories were propagated. Legends have recounted stories of ancient priestesses punished in horrible ways for their vanity, creatures created as a result of forbidden rituals and some even have it that Medusae are the offspring of mankind and demons. While none of these stories is actually true, they do reflect the fact that Medusae are not regarded as a natural phenomenon, in fact, that their very existence is the result of a perversion of nature. This aspect of these stories does in fact reflect reality.
Recent research conducted with the help of daring adventurers has shed a great deal of light upon the origin of Medusae. It has been discovered that they are in fact elemental creatures of earth. They are, or, more accurately, were spirits of nature and earth, probably closely related to dryads. Such spirits are known to be bound to specific places. Their appearance and nature is a reflection of the place they are bound to. While this is their strength it is also their vulnerability, as, if their home should become corrupted, the nature of the spirits bound to it becomes corrupted also. This is often a traumatic event for the unfortunate spirit, and if it does not result in the spirit's death, it is likely to drive it to madness. In the process of this change, the spirit is torn free of its link to its homeland, and is released to roam the land, spreading chaos and destruction in its wake. A tragic fate with tragic consequences.

The myth of the Medusa's hideousness is greatly exaggerated - in fact it is the corruption and madness that ravages the former beauty of these creatures that creates the impression of ugliness. It is certainly not the mere sight of these beings that turns living beings into stone. Medusae are capable of petrifying their victims because they are magical beings, imbued with elemental powers which are a remnant from their previous lives, now sadly corrupted like the rest of their being. Driven by their madness and an unbearable sense of loss, they cannot bear to see beauty and attempt to destroy and corrupt what was once sacred to them to alleviate the pain they are suffering. This mentality makes them the natural consorts of demons and all things evil.
Sometimes demons purposely desecrate holy sites of nature to force the creation of Medusae but that process more often then not just leads to the demise of the earth spirits. Medusae themselves are much more proficient in corrupting such places while corrupting the bound spirit as well in the process. So sometimes small covens of Medusae are formed and some of them have even managed to carve themselves a niche in the demonic hierarchy.