San'Shyuum

San'Shyuum (Latin perfidiae vermes, meaning "worms of treachery"), also known as Prophets by many individuals, are a sapient species native to Janjur Qom. The San'Shyuum serves as the leadership caste of the Covenant and exert complete control over the Covenant's religious and political affairs.

Anatomy and physiology
Regarded as a highly intelligent race, the San'Shyuum are a gangly, bipedal species, with very long, serpentine necks and limbs. With an average height of 213.4 centimeters (7 feet) to 226.1 centimeters (7 feet and 5 inches) and an average weight of 81.4 kilograms (179.4 pounds) to 96.6 kilograms (212.9 pounds), the San'Shyuum are a tall and lithe species. San'Shyuum have frail skeletal structures which require slow and delicate movement. Members of the species generally have elongated heads, with prehensile, salamandrine lips. The slick skin of the San'Shyuum changes complexion with age; younger members of the species have light brown skin, with the complexion paling with age. Hair sparsely covered the body of a San'Shyuum, though many individuals had most, if not all, hair removed from their bodies. San'Shyuum have two large, amphibian-like eyes that vary in color among individuals, including shades of violet, brown, green, and blue. One San'Shyuum may have two distinct eye colors; having one dark green eye and one deep blue eye was once considered to be auspicious among San'Shyuum, but now denotes the individual as a member of a genetic line that was overbred. Young adult San'Shyuum have shorter necks, more prominent noses and chins and closer eyes than their elder counterparts, resulting in a marked resemblance to humans, enough for the two species to find one another attractive. San'Shyuum blood is colored red and differing blood types exist among the species. According to human designations, one of these types is referred to as E+.

The San'Shyuum evolved on the low gravity planet of Janjur Qom and tend to have some degree of difficulty moving in higher-gravity environments. Although younger San'Shyuum are significantly stronger and capable of walking upright. Even though the majority of San'Shyuum in the Covenant are younger, San'Shyuum have a life of physical inactivity, which leaves most of the Covenant's San'Shyuum withered and weak. As a result, most San'Shyuum wear some form of anti-gravity device. However, they are still capable of moving unaided, if only for a brief period of time. Prehistoric San'Shyuum were typically very lithe and muscular; both the Forerunners and humans considered the San'Shyuum to be very beautiful.[22] After their surrender in the human-Forerunner wars, the San'Shyuum began to place their trust in the wisdom of often-paraplegic elders, though their warriors retained the musculature for which their species was renowned.[61] Millennia later, the San'Shyuum Reformists would come to adopt a similar sedentary lifestyle, although the Stoics who inhabited Janjur Qom remained noticeably more healthy and fit due to the planet's higher gravity and their genetic diversity. Some records suggest that the prehistoric San'Shyuum were genetically manipulated by the Forerunners at the end of the human-Forerunner wars, resulting in an unfortunate physical reduction of their species as punishment for their alliance with humanity.

San'Shyuum have distinct, often fur-covered, lobes of skin hanging underneath their chin similar to a beard, known as "wattles". Typically, only when an individual was deep into adulthood did a wattle weigh enough to slump down to their chin. As a result, the majority of younger San'Shyuum did not have prominent wattles, at least not under their chins. San'Shyuum also have fleshy, hanging appendages on either side of their head; despite their resemblance to ears, San'Shyuum ears are actually lobeless and located on the backs of their heads.

San'Shyuum are tridactyly-fingered—meaning that they have three digits on each hand, including a shorter thumb—with narrow, highly tactile hands. They are capable of, though typically unwilling, using handheld weaponry. Their prehensile, gnarled feet have three toes each, which are bent backward so that a San'Shyuum's weight is balanced on the knuckles of its feet. Their feet are often atrophied to a point of uselessness. This unconventional foot structure further complicates their movement when they are not being supported by anti-gravity systems.

Role Within the Covenant
"High Prophet" The San'Shyuum made up the ruling religious caste of the Covenant Empire. The San'Shyuum held a vital position in the Covenant because they were solely responsible for studying the holy Forerunner artifacts and using them to develop new technologies, and also because they managed political affairs and maintained order in the Covenant. San'Shyuum High Councilors held over one hundred seats on the Covenant High Council, sharing this responsibility with the Sangheili. The primary goal of San'Shyuum within the Covenant was to locate, study, and incorporate Forerunner technology to fully understand and advance the Great Journey. Covenant society as a whole was based on the expectation of the San'Shyuum leading the other species of the empire to transcendence. The Covenant's ruling caste appeared to encompass both the San'Shyuum and the Sangheili, though the San'Shyuum ultimately had more power within the empire as they were believed to be "the voice of the Gods".

At any given time, the Covenant is headed by a triumvirate of San'Shyuum, known as the Hierarchs. Although the High Council had an equal representation of both the San'Shyuum and Sangheili, the Hierarchs that led the council ultimately dictated all policies and decisions. Below the Hierarchs, the High Councilors of the Covenant determined legislation and executed the day-to-day affairs of the government. Ministers, whom also held office as High Councilors, headed the ministerial bodies that made up part of the Covenant's executive branch. Vice ministers serve as the deputies to their ministers, substituting in for their minister on the High Council if they were unable to attend a session. Senior and junior staffers were positions within a ministry, serving to aid their superiors in dealing with ministry matters. Early in the Covenant's history, San'Shyuum once held a more active position within the military, serving as starship captains, gunners, and officers. Eventually, the military was under near-total control of the Sangheili,[42] though the San'Shyuum held seats on the martial Council of Masters.

As the representatives of the gods, the Prophets held a great amount of power over the other races of the Covenant, earning reverential titles such as "Holy One" and "Eminence". They were protected at all times by legions of Honor Guardsmen, whom would loyally defend the San'Shyuum to the death, and rarely involved themselves in combat, preferring to dedicate themselves to studying Forerunner artifacts. However, important events to the Covenant usually required a high-ranking Prophet, such as a Hierarch, to be present. Both the architecture and the structural aesthetics of weapons and vehicles of the Covenant was predominantly San'Shyuum in nature and design, with Sangheili architecture conforming to the San'Shyuum's preferences over time.