The tirapheg is one of the sillier monsters from 1st edition AD&D's Fiend Folio.
This is its story, fitted into the world of the Age of Worms Adventure Path.
Tirapheg
Tiraphegs are abominations first created by the Ebon Triad cult as part of their blasphemous experiments in merging three gods into one. Tiraphegs are merely mortal, created from human prisoners and stitched together using surgery and vile magic, but the cultists saw them as an essential step toward creating the Ebon Aspect, a terrible fiend that is to date the highest manifestation of their arts.
The first tiraphegs were created by Lashonna, the founder of the cult, with the aid of the avolakia Mahuudril, and the dungeons beneath Alhaster are still home to large numbers of them. Perhaps Alhaster would have been the only home of this deformed new race if Lashonna hadn't given the secrets of creating them to other cultists in the hope of speeding their research. Tiraphegs are also (at least at one point, though many have died out) found in caves near the Black Cathedral in the Diamond Lake region, and beneath Castle Greyhawk in chambers beneath the Tower of Magic. Beneath Greyhawk Castle, the mages Sindar Sirion, Zelcon, and Ussisemeel had close secret ties to the Ebon Triad cult as heretical devotees of Vecna, Hextor, and Erythnul respectively, and created many tiraphegs in the Vaults of Creation during their time beneath the ruins. Some still survive today, and it their presence there that has given rise to rumors that tiraphegs were mad experiments of Zagig Yragerne himself. These rumors are false; even Zagyg's sense of humor was never so twisted. Tiraphegs may conceivably be found elsewhere as well, as far south as the Amedio city of Cauldron; the Ebon Triad has spread far and wide.
To be a tirapheg is to be in constant pain. Mahuudril saw no point in dulling its prisoners' ability to feel agony as it stitched them together, nor in making their lives comfortable afterward. Each tirapheg was made from three prisoners; three arms, three legs, and three heads were stitched to a single torso and magically kept alive. Only the central head was allowed to retain eyes, two in the front of its face and one behind. The mouths of all three heads were stitched shut and made to heal together until only a faint scar remained. In keeping with the cult's obsession with the number three, the central arm was given three fingers and the central leg was given three toes, while the creature's other two legs were left as mere useless stubs and its other two arms tapered into sharp spikes. In the center of their torsos, beneath their third arms, tiraphegs were given large, obscene mouths, around which writhe three wormlike tentacles. These mouths and their associated digestive apparatus are suited only for a diet of decayed flesh, forcing a tirapheg to share an ecological niche with ochre jellies, otyughs, and similar subterranean scavengers. The first meat a tirapheg is given is composed of the limbs and torsos that were discarded in its own creation.
As part of their role as stepping-stones in the manipulation of divinity, tiraphegs were invested with one magical gift: the power to create harmless illusionary duplicates of themselves. The intent was simply to learn how creatures such as they might be invested with permanent magic in preparation for greater experiments later, but tiraphegs are sometimes able to use their simple illusions to frighten off or distract would-be attackers.
Tiraphegs are technically hermaphrodites in the sense that they were created from both male and female prisoners, but they do not retain anything resembling genitalia. Mercifully, they are unable to breed; if further experiments did give them reproductive abilities, their offspring would likely be ordinary humans.
Obviously, the design of the tirapheg reflected the warped religious symbolism of the Ebon Triad cult and was never meant to be anything that would easily be able to survive in the wild. The miserable creatures can barely walk on their single feet, shuffling through the dungeon corridors in short hops while their stub-legs swing uselessly at the sides or, more commonly, giving up any attempt at walking and simply writhing across the floor like worms. Without cultists keeping them supplied with flesh, most quickly die, and in places they have survived the departure of their creators (such as the ruins of Castle Greyhawk), it is because other twisted denizens have decided to keep them fed for reasons of their own.
As essentially failed experiments, tiraphegs likely would have been euthanized after their value as teaching aids had ended. However, as they are still essentially human despite their magical and surgical alterations, the cultists found them valuable as test subjects for a variety of rites that involve the manipulation of the human form. As such, there are many variant tiraphegs as well, including a variation that spits Kyuss worms from its torso-mouth and a variation that casts Evard's black tentacles at will. These special experiments are normally thrown into the same pits, cells, and corridors as unaltered tiraphegs, so those who come across them will have no simple way of distinguishing the experiments from the others.
Tiraphegs cannot speak and they have developed no other way of communicating, but most can understand Common. In theory, a tirapheg could write, but most have become quite mad after years of conjoined existence in the darkness feeding on corpses and have no inclination to figure out how their deformed central hands might manipulate a writing implement. As experiments of a heretical religious cult, in theory tiraphegs belong to the Ebon Triad faith, but most have little knowledge of their captors' dogma and no inclination to embrace it for their own. Demon lords do not consider seeking converts among the tiraphegs to be worth the effort.
It is rumored that the decapus and ubue (Palace of the Silver Princess, original version) are further experiments by the Ebon Triad.
