Demogorgon (Dungeons & Dragons)

In many campaign settings for the Dungeons & Dragons role-playing game, Demogorgon is a powerful demon prince. He is known as the Prince of Demons, a self-proclaimed title he holds by virtue of his power and influence. Demogorgon lives on the 88th layer of the Abyss, known as The Abysm, Brine Flats, or Gaping Maw. The hatred between Orcus and Demogorgon is legendary. He is also a dedicated foe of both Graz'zt and Fraz-Urb'luu. In Gary Gygax's Gord the Rogue series, he is the brother of another demon lord called "Mandrillagon."

Description
Demogorgon appears as an eighteen-foot tall, reptilian (or amphibious) hermaphroditic creature with a somewhat humanoid form. Two baboon heads sprout from his twin snake-like necks, and his arms end in long tentacles. Demogorgon's two heads have individual personas, called Aameul and Hedradiah. They strive to dominate each other, but are unable to achieve control because they are aspects of one another.

Demogorgon can hypnotize with a gaze or drive enemies insane. His whip-like tail has the ability to drain the life energy right out of a living foe. His tentacles cause living creatures to rot away, as if by some sort of rapid leprosy.

Cult of Demogorgon
Demogorgon's cult is relatively small compared to "true" deities, but much larger than those of most fiends. He is worshipped not only by evil humans, but also by the intelligent rays known as ixitxachitl.

Demogorgon in Greyhawk
In the World of Greyhawk campaign setting, Demogorgon sometimes goes by the ancient name "Ahmon-Ibor," or "the Sibilant Beast." He is responsible for corrupting the paladin Sir Kargoth and transforming him and thirteen of his fellow Knight Protectors of the Great Kingdom into Oerth's first death knights.

Demogorgon in Baldur's Gate
In Baldur's Gate II: Throne of Bhaal, part of the Baldur's gate series of computer role-playing games, Demogorgon appears imprisoned in the dungeon known as Watcher's Keep. The player quest was supposed to seal the dungeon to keep Demogorgon imprisoned, but can also kill Demogorgon, sending him back into the Abyss.