Yaoguai: also known as Mutants or Guai, they are an multi-race species made from victims of various species that went through an Dark Side ritual that merged the bodies of the victims with the spirits of dark side demons, turning the victims into monster. They act as an auxiliary force to the Legion of Darkness and various Dark Cult cults. There are three types of Yaoguai: Lesser Yaoguai, which are the main force, Yaoguai Chief, which acts as officers or commanders, and Yaoguai Kings/Queens, who are the leaders of various Yaoguai tribes.
(Made from the Possessed from 40k. What do you think @AstralFists )
Sithblade: bladed Weapons that have been injected with dark side demons, transforming them into eldritch weapons that caused mass terror, mass torture, mass destruction and more. Swords, axe, butcher swords, etc., all bladed weapons are incredibly dangerous and are promptly destroyed once retrieved by any Jedi who acquired these weapons.
Humanity in the Pre-Imperial Era has been long divided and separated, many worlds being unaware of each other, and the worlds that are aware of each other, would often go to war with each other, the only time humanity is ever united on something was during their wars with the Rakata, and after the Rakata die out, humanity went back to being divided again. Their sub light travel is to blame here, as their lake of a Hyperdrive and Kuatfield has led to human expansion to be very slow, with many generations often being passed before the sleeper ship reach their planet of destination, however, it all changed with the invention of the Hyperdrive.
In 21 BFI, among the best Magisters* of Corellia have reversed engineered the Rakatan Hyperdrive and Kuatfield, allowing humanity to finally traverse Hyperspace without fear of being torn apart by Dark Side Demons, it still has the caveat of requiring Force-Sensitives to properly pilot it, though their re-engineering have made it so that any force-sensitive can use it, instead of just Dark Side users, the discovery of such vital technologies helped travels that would otherwise take decades or centuries take mere days or hours, however, true unification would not come until the rise of the First Emperor…
Little is truly known about the life and story of the First Emperor, as much of it was mythologized by the Galactic Imperium way after his death, and even conflicting accounts of how his life was like, what is known is that he was elected as king of Coruscant through its elective monarchy in 1 AFI, from which he proclaim himself emperor and and the formation of the Galactic Imperium.
Taking advantage of the new Hyperdrive technology available to humanity, he then carried out a series of military campaigns now known as the Unification Wars, which saw a vast amount of planets in the Segmentum Corus, or the Core Region unify under the Galactic Imperium, the First Emperor have raised a formidable army, Corellia, one of the allies of the Coruscant, produces much of the walkers and ship needed for the conflict, while Alderaan and Coruscant itself provides legions upon legions of Infantry Guardsmen, another factor helping the First Emperor and his allies is his Imperial Trooper Project, a project involving the genetic augmentation of recruits in order to form the elite soldiers of the Galactic Imperium.
Eventually, all of the human settled core worlds is unified under the Galactic Imperium, along with the Duro which are also native to the Core, and the First Emperor went out to the Colonies Region of the galaxy, mainly through the Corellian and the Perlemian trade routes, however it is through the Perlemian that the Galactic Imperium would find an organization would soon become critically important to galactic history…
The Jedi Order are one of the descendants of the remnants of Je'daii Order which have survived the tragedy of Tython, becoming resentful of the Dark Side of the Force as a result, their headquarters was stationed on Ossus, which is also where the Galactic Imperium found them in 34 AFI, the First Emperor offered them a deal, the Jedi are free to practice their religion in peace, and in return, they will serve as the keepers of the peace, ensuring stability in the Galactic Imperium, as well as serving as auxiliaries if need be, the Jedi accepted the deal, causing them to become one of the most loyal allies of the Galactic Imperium.
Eventually though, the First Emperor would die of old age, his body stored beneath the Imperial Palace, and with a new elected emperor taking his place, at his death, he left Coruscant a capital of an empire, and while he may have died, the empire he helped create lives on, eventually uniting the known galaxy, and laying the groundwork for order and protection from the many threats that emerge in the galaxy…
*: thanks to @Archon7 for the inspiration for coming up with that name
Black Steel Enclave: a paramilitary organization consisting of ex-soldiers, pirates and mercenaries that rivals the major criminal organizations like the Hutt Cartel and the Black Sun. Their origins is a rather sad tale, residing in the first and only Crime Wars. The GI, seeking to rid the galaxy of crime lords, set out a major military campaign to destroy the crime lords in the Outer Rim. The Black Steel Enclave, known then as the 44th Infantry Battalion, along with two other units, 101st Mechanized Division and the 69th Jedi Regiment, were among those involved in that War. Under the command of General Dow-Fal, the 44th, 101st and the 69th were attacking an major industrial planet when the Crime Lords offered an treaty, which they offered to give the GI 10 percent of their entire territory in exchange of being left alone. Dow-Fal, agreeing to orders to stand down, left his men on the planet to die due to his older brother in the 44th down there in the fighting. He wanted his brother position as Senator so he left him there. The 44th, 101st and the 69th felt betrayed, managing to conquer the planet and defected from the GI, reforming all three groups into one group, the Black Steel Enclave. Dow-Fal was arrested and executed for his crime of abandoning his men while the Enclave started recruiting ex-soldiers, and mercenaries from across the galaxy. As of today, they are still in war with the crime organizations, along with raiding the GI for their resources and weapons, as well as attacking outposts of the Legion of Darkness and destroying them.
Black Guards: an elite unit with the Enclave. Years are spent training a single soldier of the Black Guard. A single Black Guard soldier is equivalent to a platoon of GI Guardsmen or Legion of Darkness troops. They also acts as commanders to the lesser ranks of the Enclave. Armed with both melee and ranged weapons, including rifles, electro-hammer/staff/batons, auto-blasters, grenades, as well as modified primitive weapons like explosive crossbows. they make use of specialized shuttles to transport them to places.
In addition, there are several ranks within the Black Guard:
Black Guard Conscript: rank-and-file of the Black Guard
Black Guard Guardsman: standard forces of the Black Guard
Black Guard Trooper: elite of the elite.
Black Guard Chaplain: support units
Black Guard Devastator: heavy troops
Black Guard Captain: officers of mission operations.
Black Guard Commander: only eight of them can exist as they are the second-in-command of the Black Guard
Black Guard Lord Commander: the overall leader of the Black Guard and second in command of the Black Steel Enclave.
The Basics of Hyperspace Travel and Communications
Hyperspace, despite being inhospitable towards life, is ironically one of the only things allowing galactic civilization to even exist, as without it, the FTL travel would be impossible, the very nature of the realm allows this, as one can travel several light years in a short amount of time, however, the chaotic nature of Hyperspace means that ships would need to have certain technologies to be able to pass through it unharmed.
One of the essential technologies to have for Hyperspace travel is the Hyperdrive, a device that allows ships to enter Hyperspace in the first place by opening a portal from the Material Realm to the Immaterial Realm, however, ships entering Hyperspace would be subject to incursions by Dark Side Demons, who would tear apart the ship and torture the ship's crew, for this, the Kuatfield Generators are important, named after the former Coruscanti continent of Kuat, which is now a name of a planet, the Kuatfield Generator protects the ship from Demonic Incursions by generation a Kuatfield, a bubble of anti-Force for a lack of a better word, around the ship, this device would needed to be maintained at all times, as for if the Kuatfield flickers for even 1 second, Dark Side Demons would come in and rip apart the ship.
The pilots of these ships would the Force Navigators, Force-Sensitives who are navigate through the chaotic realm by using the Force to find the route to the destination the ship needed to reach, the Force Navigators of today consists of Jedi Order Members who specialized in Force Navigation and precognition.
Interstellar communications is also equally important, thus, another important group of Force-Sensitives are the Force Receivers, who dwell in Receiver Stations dotted around the galaxy, and who receives signals sent through Hyperspace by ships or some source, they would then send to a Relay Station, where a small group of Force Receivers would sort, identify and logged the signals they receive, before sending to its intended destination, just like Force Navigators, the Force Receivers of today consists of Jedi Order Members, albeit specializing in astro telepathy.
(This would be one of the couple exposition posts I would have to make in order to get the general knowledge stuff over with before I actually continue with the timeline)
Juggernaut: The Black Steel Enclave's answer to the Imperial Storm Warrior. Not actually Storm Warriors, they're Exosuits designed to mimic the capabilities of the Storm Warriors. Armed with either an heavy rotary slug thrower or an heavy auto blasters, and have two clusters missile pods on each shoulder designed to blind enemies. Originally used by high-ranking commanders, the exosuits are slowly becoming more common, with Captains finally having these exosuits.
Psion: When the 69th Jedi Regiment became part of the Black Steel Enclave, they renamed themselves as Psions. When they detect Force-Sensitive within Enclave's territory, they offered the family large compensation in exchange of taking their force-sensitive children away and train them. An small percent of the Psion becomes Psion Navigator and Psion Receiver. Due to the limited number of lightsabers available due to defecting from the Jedi Order, only commanders and the leader of the Psions themselves can have lightsabers. There are several type of Psions.
Psion (rank): the standard soldier armed with an blaster and vibro-knife
Psion Flayer: officers of Psions forces armed with either a shotgun blaster or more rarely, an lightsaber.
Psion Retiarius: a specialized and extremely rare type of Psion who uses the dark side to create traps. Collared with a bomb collar in the event they became insane.
Psion Murmillo: another specialized Psion, though more common than the Reitiarius, that create force barriers for their allies. Often armed with a sniper blaster.
Psion Hoplomachus: this specialized type of Psion was the first group of force users to create wave based force judgements attacks. Extremely rare and more often act as commanding officers for raiding or in high-level operations.
Psion Optus: Commanders of various forces of Psions.
Psion Freeborn: originally the commanding officers of the first generation of Psion, they became the Psion Council. Twelve members in total with the thirteenth member being the grandmaster of the Psion, or Freeborn Prime
Psion Freeborn Prime: the grandmaster of the Psion themselves