In Greek mythology, the gorgons were three monstrous sisters whose visage turned people to stone. Detailed descriptions vary, although they typically had snakes for hair. In D&D, however, these beings are known as "medusas", from the name of the specific gorgon slain by Perseus. The creature known as a gorgon in D&D is therefore, something else entirely, an essentially original creation, albeit still with the power of petrifaction, and perhaps partially inspired by the bronze bulls from the story of Jason and the Argonauts.
Like their supposed enemies, the blink dogs, displacer beasts have been present in every version of the Dungeon & Dragons game. Apparently based, at least in terms of their physical appearance, on an alien creature featuring in the works of early science fiction writer A.E. van Vogt, their signature power is nonetheless original to the game. They are among the few standard D&D creatures not to be included in the Open Game Licence, so that they are distinct to that game and not to any of its clones/adaptations, such as Pathfinder. But we're not restricted by that here, since we're just providing a review of the thing. So what can we say about them?