Armanites were a form of centauric tanar'ri that served as the heavy cavalry of demonic armies, furiously charging into battle with savage bloodlust. When not racing across the blasted plains of the Abyss in disorganized mercenary companies, armanites surged out from its infinite depths to make war with all that was lawful and good.
Armanites looked like undead centaurs with ram or bull horns sticking out from their their brows, standing 6 feet (1.8 meters) tall at their haunches and 10 feet (3 meters) tall overall. Their hauntingly pale complexions were made more eerie by their sagging stomach flesh, with older armanites looking practically gutted. Their seemingly sickly upper halves were covered with festering sores, while their lower halves were more muscular, contributing to their astonishing weight of 2,600 pounds (1,200 kilograms). Their tails were long, serrated, and covered in the same stiff bristles and spines that constituted their manes, which protruded out from the gaps in their armor. Curved claws and spiked hooves made them all the more terrifying.
All wore full-plate armor that was constructed of demonic chitin and heavier than it might first appear. The black, fluted barding they wore seemed to be more ornamental than utilitarian in purpose.
Some armanite breeds had kangaroo-like lower halves with hands as opposed to front legs, capable of manipulating small items, and weaponry.
Armanites fully understood their role on the battlefield and savored it, acting with bravery that bordered on foolishness. However, their preferred jobs were ones that offered them the greatest amount of bloodshed with the least personal risk. Despite their excellent service they were also arrogant and fickle beings that were not shy about leaving a battle even at its climax. If not rewarded the plunder they expected for their services, or if given orders they didn't like, they would desert or even rebel against their employers.
Armanites were clannish and territorial demons that forbade any trespassers within their lands. However, though they exercised coordination and discipline admirable by even their hated baatezu foes, armanites were in no sense creatures of order. They were disorganized and quarrelsome, brawling amongst each other when no other enemy was available, and they greatly enjoyed the chaotic nature of group combat. They found such conflict far more preferable than individual duels or competitions of skill, and upsetting one was likely to provoke an entire troop. They were at their most dangerous when not actively engaged in plotting or conflict, as they were not currently expressing their bloodlust yet and were eager for targets.
Armanites were practically living weapons with their sharp hooves, talons, and tails allowing them to rip their foes to pieces with ease. Outside of their natural weaponry, more powerful armanites could let loose lances of lightning against their enemies.
Armanites could also fly by galloping into the air for a maximum of one hour a day. They began flying slowly into the air, seemingly running up an invisible hill, and could not stop or quickly change directions while they did so. If the need arose, armanites could summon a small crowd of dretches or another armanite to their aid.
In addition to their natural weapons, many armanites were walking armories, wielding many different weapons kept immaculately clean and covered in Abyssal runes, ranging from crossbows, composite bows, shortbows, lances, halberds, sabres, flails, longspears, flanged maces, and flamberge swords.
Although tactically efficient and able to cooperate, armanites depended on the speed of their stampedes rather than timing or planning. They were efficient as mobile shock troops, striking with stunning speed before retreating and striking again. Their aerial charges especially were effective against foot soldiers, and designed to wreak maximum mayhem and carnage.
After wading into combat they normally switched from their spears or lances to other melee weapons like flails, wildly kicking and rending their opponents throughout the battle in whirlwinds of destruction. If pressed by sturdier oppositions they attempted to use their lightning abilities to blast their foes apart.
The 377th layer of the Abyss, the Plains of Gallenshu, was the dwelling place of most armanites, a series of massive plains constantly tread by huge herds of their kind. The layer was run primarily by the armanites, who functioned in independent companies and were willing to work as guards, scouts, messengers, or otherwise spread mayhem and acquire loot. Most herds of armanites were specialized in specific tasks, like foraging, archery, skirmishing, and other war related skills. They might also equip others for warfare but they never conducted sieges. They had high costs for their services, starting at 100 gold pieces a day and only going up from there.
All armanite packs were disorderly, but were commanded by a charismatic leader who controlled the group through threats and promises. Most armanites not only served, but worshiped their respective warlords, who often encouraged the formation of these cults. These singular leaders were known as Knechts or "Pathwardens", and often provided ranged support to their packs. The loss of a pack's Knecht resulted in the armanites rampaging until they were stopped or a new Knecht arose. It was much more common to find lone armanites than small groups, as those were almost always the results of failed raids, and with nothing left to fight they often turned upon each other.
Sycophants who took the proper initiative had the near-suicidal honor of carrying a herd's standard into battle. Every herd of armanites possessed a troupe banner and a banner of their current warlord, such as a diagonal black-and-white slash for Graz'zt or a golden talon with a dark red background for Pazuzu. A troupe banner was a unifying symbol amongst armanites and losing it in battle prompted the same response as losing a Knecht, causing most troupes to feud and disband before either joining forces with one of the lords from the Plain of Infinite Portals or simply aligning with another troupe.
Armanite towns were run by beings known as Konsuls, masters of up to 100 packs. Some Konsuls were capable spellcasters, and rumors had it that priests were also within their midst. Twenty-four towns of the armanites were known in Gallenshu, including: Amber, Basalt, Bloodstone, Bone, Clay, Cold Iron, Dark Spring, Gray Glass, Jade, Mageblood, Maroon, Obsidian, Ochre, Oxblood, Purpure, Silver Spike, and Steelshank. The other seven were run by female armanites, and were small camps of tents, carts, and large, wheeled towers. Mobile towns frequently changed their names while the named ones were stationary. Armanite towns were essentially stables used to regroup, and rearm before engaging in the next big battle.
While rebel armanites were normally buried underneath a leafless tree, crippled or weak armanites were put down like horses or enslaved. Those slaves that worked as smiths sometimes earned a reputation great enough to earn the attention of significant Abyssal figures, and were taken by these beings for work. This was known as a Bitter Emancipation by both the slaves and former slavemasters, as not only did their herd lose a capable craftsman, but the slave might end up getting turned into a mane if they failed to produce amazing works. Outside of weapons they were also known for being excellent farriers, making outstanding and sometimes magical horseshoes, and some of the best yokes and harnesses in all the planes, Puffed and slashed cloaks, colorful flags, and battle standards were also well-made pieces.
Armanites often worked as special operatives for demon lords due to their excellence when working in independent packs. Territory and soul larvae were also acceptable methods of payment from their Abyssal masters. The denizens of the Upper Planes referred to them as Dark Horsemen or Darkriders and feared their presence, and they were also hired to serve as bodyguards within Sigil.
Armanites loathed and often abused least tanar'ri, including manes, dretches, and rutterkin, although rutterkin were infrequently taken into armanite herds to serve as servants, smithies, grooms, and auxiliary riders. A hezrou might work with a troop, but they also refused to cooperate with bulezau demons.
Armanites came into existence either from being born from male and female armanites or ascending from weaker tanar'ri. Female armanites made up a third of the population and the two sexes were segregated as fighting was almost inevitable if they were allowed to mingle amongst themselves. Herds of different genders joined together after a victorious battle against the baatezu, whereupon mating occurred.
Young armanites were simply herded along with a camps servants and other followers until they seized a weapon from a deceased troupe member and vanquished their first opponent although many were abandoned and they received no special care. They reached maturity after approximately a year. 
Both the body and spirit was consumed by armanites, a substance legends purported they enjoyed above all others. This process could leave someone incapable of being resurrected. Their favorite foods consisted of Abyssal bats, baatezu, and yugoloths, in that order.
The first armanites were from six clans of Feywild centaurs that had been enslaved and twisted by fomorians before escaping and stumbling upon a portal to Pazunia. After time spent in the realm of demons some turned into demons themselves, abandoning their proud heritage in favor of becoming abyssal mercenaries.
During one of the hotter points of the Blood War, many armanites worked with the similarly blood-crazed bulezaus of Baphomet, and their combined assaults were core to the defeat of Hell's legions. When the equally violent demons attempted to claim the spoils of war, conflict broke out on who would take what. The grudges from these battles are still seen in the inability of both demons to cooperate. Although some armanites within Gallenshu still worshiped Baphomet, many switched to serve under demons like Demogorgon or Kostchtchie, with bands who worked with the Horned King being rare and usually doing so briefly.
The demon lord Graz'zt was known to employ a group of eight armanites—four white and four black—to draw his carriage.
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