A gorgon (from the Greek world "gorgos", or "dreadful") is a female mythical creature of various descriptions. The original gorgons were a trio of sisters, Stheno, Euryale, and Medusa, who had snakes for hair, scales, and brass claws. Medusa is the most famous of the three (as well as, in some versions of the story, either the only one with the stone thing or the only one who was mortal/killable), but the gorgon species lives on in the bestiaries of role-playing games.
Dungeons & Dragons
In Dungeons & Dragons (and the Pathfinder Roleplaying Game) gorgons are not snake-like at all. Instead, they are depicted as massive bull-like creatures covered in metal scales and plates (though they are fleshy underneath). Gorgons are also capable of turning people to stone, but unlike classical gorgons, they do so with their breath rather than their gaze. This probably came about because they used the name of Medusa to cover the entire snake-woman gorgon species, and because Gygax likely read or owned a copy of Edward Topsell's The Historie of Foure-Footed Beastes, a 17th-century bestiary which is the only extant pre-D&D literature to list the gorgon as an armored bull with poison breath. Topsell's bestiary, in turn, seems to have misappropriated the name Gorgon for a bovine creature which combines features of the catoblepas (a poison-breathed bull monster which is also featured in the Monstrous Manual) and the Khalkotauroi (a pair of bronze-hooved, bronze-mouthed, fire-breathing bulls forged by Hephaestus), creating the scaly bull-monster with petrifying breath that we know today.
Gorgons have been with D&D since the beginning. They received a more thorough Ecology write up in Dragon Magazine #97. Gorgons stand six feet tall at the shoulder, and are eight feet long. They are said to be always angry, all the time. Like other bovine, they are herd animals. Unlike other bovine, they are omnivorous and will frequently take carrion or live prey in addition to grazing vegetation. Gorgons are said to be far too ornery to ever be tamable, and despite their assholish nature they aren't intelligent enough to register morality. Gorgons are neutral, like a force of nature. They don't care what they fuck up, but wherever they are they must fuck shit up. This could lead to some rage-worthy situations where your resident That Guy, paladin of Stupid Good refuses to engage them when they don't ping on his evildar while they mercilessly proceed to turn the whole party into a statue garden.
A notable exception is the Birthright setting, where the Gorgon is one of the top BBEGs. Once Prince Raesene, eldest son of the first lord of House Andu, he always resented that his illegitimacy meant he would never take the throne himself, despite still being loved and respected by his parents and brothers. Ultimately, Azrai saw the growing envy and lust for power in his heart and corrupted him into his service, seducing him into betraying his family and taking his core retainers into battle alongside the dark god.
After the other gods blew themselves up to take Azrai with them at the Battle of Deismaar, Raesene absorbed more of the gods' essence than anyone present who did not then immediately go on to become a nascent god themselves. In the coming years, he carved out his own kingdom in the north, discovered bloodtheft, and began cultivating and "harvesting" bloodlines to increase his own strength. He ultimately killed his brother's descendant, Michael Roele, in battle, but in the process Michael may have managed to turn the tables on him, warding the majority of his power to weaken Raesene, confining him to his keep so that he doesn't dominate the entire campaign setting.
Either way, there's not much humanity left in Raesene, who is now called the Gorgon. A stone-skinned, horned monster with digitigrade legs and spikes sticking out of his flesh everywhere, the Gorgon is the greatest swordsman in the world, master of the strongest holding in the world, has access to huge reserves of mystical power and a gaze attack that can kill or petrify anyone without the saves to shrug it off up to twice in a round. While unlike many awnsheign the Gorgon can be killed in a straight-up fight (assuming you have magical weapons of sufficient potency to penetrate his immunity), he is unaging and terribly, terribly patient. He is driven by a lust for power and thwarted ambition, and hungers to become emperor of the entire continent, then, perhaps the entire world. He also has a court full of equally-deadly and capable figures, and he is in an alliance with the Magian and the Raven, inasmuchas they agree they'll need to bring the other, more chaotic awnsheigh to heel before battling one another for control of the continent.
- Ferrus Manus, the Primarch of the Iron Hands, was nicknamed "The Gorgon" (incidentally, his homeworld is named Medusa).
- The Gorgon Armored Assault Transport is a super-heavy transport used by the Imperial Guard of Warhammer 40,000.
- Hive Fleet Gorgon. Originally part of the Behemoth Hive Fleet, but survived as splinter fleet and grows into a hive fleet after nom'ed its way to Eastern Fringe. Known for being the first hive fleet encountered and defeated by the Tau Empire.