Yak Folk, originally known as Yak Men and who call themselves Yikarians, are a minotaur-like race of humanoid yaks native to the lands of Al-Qadim and characterized by their high intelligence, their natural affinity for magic, their ability to possess the bodies of others, and their brutal, slavery-based culture, which centers around religious subservience to a nameless dark god that demands constant human(oid) sacrifice.
Yak Folk are very much similar to minotaurs; they appear as ogre-sized humanoids covered in a dense coat of coarse fur, with yak-like bovine heads and digitigrade legs ending in hooves. Males and females are difficult for outsiders to tell apart. Their human-like hands end in relatively dainty and nimble sets of five fingers, hinting at their affinity for spellcasting. They typically wear long, flowing robes, and occasionally turbans, and are usually festooned with magical items - especially magical rods and staves, which they have a strange obsession with.
The culture of the yak folk is a weird mixture of a malign theocracy and a malevolent magocracy. All yak folk have some level of affinity for sorcery, mostly manifesting in their innate ability to use magic items back in AD&D, and their leaders are always spellcasters with access to both arcane and divine magic. They also have (or at least had, in AD&D) the innate ability to command dao, having somehow enslaved the entire race of earth genies to obey without question the orders of all yak folk.
Most yak folk cities occupy the peaks of the highest mountains. An average city holds several thousand yak folk, plus five or six times that many slaves. Even the poorest yak folk keeps a servant or two, and slaves are the yak folk's common currency. Buildings and other structures are made from a gray, greasy-textured stone that dao import from the Elemental Plane of Earth. The walls of a yak-man city rival those of the strongest human settlements.
Outposts of this brutal society lie in the narrow vales below the mountain peaks, each housing 11 to 20 yak folk. The numbers may seem scant, but a single outpost can dominate an entire valley, for it has the aid of 10 dao and 10 to 40 local enslaved warriors. The yak folk demand a portion of the low-land population as tribute for their "wise and benevolent" rule. Those who disagree with this attitude are destroyed. Their lands are given to slaves who are more receptive to the yak folks' will - that is, slaves willing to sacrifice a portion of their families to help ensure the remainder's survival.
Yak folk function as a unified, malignant theocracy. All are fanatical followers of their Forgotten God (a name used by outsiders; the yak folk's own name for their god is unknown). The worship of this savage deity directs their lives. The Forgotten God takes the general form of a yak-man, but the deity's face is worn smooth into a featureless mask. Great statues of the faceless god dominate yak folk temples, which occupy the highest crags of their home mountains.
The yak folk's dark deity is appeased by sacrifice, which the followers carry out by offering slaves in the "Manner Elemental" - that is by fire (immolation), earth (live burial), water (drowning), or air (throwing the victim off a mountain). Daily sacrifices ensure the ongoing benevolence of the deity. These hideous acts also strengthen the yak folk's domination of their land, since a slave who disobeys today almost certainly will meet his or her death on the morrow.
It was the Forgotten God who enabled the yak folk to enslave the dao. In a legend told by bards, it is said that the Forgotten God once journeyed to the Elemental Plane of Earth. There, through guile and deception, the deity defeated the ruler of the earth elementals. The price of that defeat was harsh: the dao were forced to serve the Forgotten God and its minions - and forbidden to attack them - for "a thousand years and a year." (It is unclear how much of the sentence has passed, but sages are confident it will continue for centuries to come.)
Of late, the rest of the world has begun to interest the yak men, who see it as asource of new slaves and power. A foray into civilized realms typically involves a single scout or a party of one to four. A dao may accompany each yak-man. If a yak-man leader is present (10% chance), then any accompanying dao is noble.
For a single scout, the mission is usually reconaissance - helping yak folk gauge the strengths and weaknesses of their potential foes. Nearly all scouts are convicted criminals hoping to earn a new life among their fellow yak folk. (If they die on duty, it hardly matters.) Should the scout return to the home city with some remarkable treasure or an extraordinary parcel of slaves, his crimes will be forgiven. These scouts frequently make deals with evil humans. A single yak-man may return home with a caravan of servants, kidnapped or stolen, or with some other treasure, similarly "hot".
A party of yak folk in civilized lands usually has a mission involving the members' magic jar abilities. They seek to kidnap a mortal or two and then inhabit their skins. (At least one yak folk guards the bodies of his or her companions.) Such spies strive to infiltrate the local ruling class; taking the place of a well-positioned servant or slave is a popular tactic. (It's more difficult to imitate someone with power or unusual ability.) After the mission is completed, when it's time for entertainment, a yak-man may force the inhabited body to run amok, spreading chaos, only to abandon control at the correct moment, leaving the confused mortal to pay the price for the yak-man's actions.
Yak folk have an inhemt drive for knowledge, particularly dark knowledge that may serve to corrupt or dominate others. Knowledge that yak folk cannot gain or use immediately is to be destroyed. Unsentimental by nature, yak folk parents pack children off to communal creches once they are weaned, never to recognize them again. yak folk feel no loyalty to their family - only to their god and to their inherently superior race as a whole.
Outsiders know little of the yak folk. For the most part they have remained within the confines of their lands, content to enslave or kill whomever enters it. To the other intelligent races, they are mysterious figures, treated as "boogie men" - a scary race of evil, ruthless, unenlightened, powerful savages who threaten the security of neighboring lands. The reputation is warranted.
All other races are slaves at best to the yak folk - even dao. There are rumors that dao leaders are working in conjunction with the Forgotten God, helping that deity facilitate its own besting other genie lords and the temporary enslavement of their races.
Yak Folk debuted in the original Land of Fate boxed set for Advanced Dungeons & Dragons 2nd edition. They then reappeared in the Monster Manual II for Dungeons & Dragons 3rd Edition, and in the adventure Storm King's Thunder for Dungeons & Dragons 5th Edition.