How to play as a Yuuzhan Vong
Overview
The Yuuzhan Vong, playable here, are a species with far too much lore behind them to condense into a single species page, but that lore is also so important for playing as one, that it had to be given a place. Hopefully, this guide of sorts will help you know what you need to know if you're going to be playing as a Yuuzhan Vong.
Here, we will be going over their culture, castes, beliefs, and the unique situation revolving around their technology. (I'll also be using the word "Vong" by itself a few times for short, but this would actually be a bit of a derogatory term in-universe, akin to calling someone an unwanted orphan.)
Roleplaying
Extragalactic
The first big thing to know is that the Yuuzhan Vong are not from the Star Wars galaxy proper. They arrived in a massive invasion force that ravaged the galaxy for ## long years. Eventually, the war ended with a revolution from within, and the species settled in the Unknown Regions, occasionally reaching out to the galaxy proper.
Depending on the era you're playing in, the Yuuzhan Vong could be unknown aliens, loathed for the sins their kind committed, or tentatively integrating into galactic society.
Technophobia
The Yuuzhan Vong culturally believe mechanical, non-organic technology, like the kind all over the Star Wars galaxy, is an evil affront to their gods. Part of their invasion was a holy war against this technology. While the reasons for this reach far back in their history, and tie in to their exclusive use of bio-organic technology, it isn't intrinsic to them as a species.
After the war ended, many of their traditions were rewritten, and relations with the rest of the galaxy saw this new age of Yuuzhan Vong at least being comfortable riding in metal ships. This is why you won't see Technophobia as an inherent trait in the species that, say, gives them disadvantage on Technology checks, anti-proficiency with blasters, or vulnerability to attacks from droids or anything like that. However, a dislike for mechanical technology, however strong, could still make for a fun character flaw in roleplay.
Biots
The biotechnology used by the Vong is referred to by them in Galactic Basic as biots, in order to differentiate it from the mechanical technology of the galaxy at large. A biot could be any device they used, as anything they used was wholly organic. Their tools, weapons, shelters, starships, etc. A lot of it is truly exotic, but at a closer look, a lot of it performs the same functions as something like a computer or some other piece of tech we're used to in Star Wars. Consider having biots require Nature checks instead of Technology.
Grafting
The higher in status and honor a Vong gets, the more they want themselves grafted to symbolize their success. Grafting is a ceremonial art forbidden to the lower castes, in which a Shaper replaces a piece of a subject's flesh with that of another creature, perhaps one the subject killed, or takes things further and completely replaces body parts with prosthetic biots that can have various functions.
Flamethrower spinal cords, parasitic bone claws, microscopic eyeballs, brain worm recording devices. These are a small amount of the sorts of grafted implants one could see in an elite Vong. Items like these do not currently exist for use in the SW5e system, but if you wanted them in your game, ideally, they would be Cybernetic Augmentation items with brand new effects that--being organic--did not make a character more droid-like as more were added on.
Techcasting
Biots do not exist in SW5e at this time, and while a Yuuzhan Vong player character can mechanically exist without access to them, this may feel underwhelming for the player. It'd be like playing as a Jedi in a game with no lightsabers. Luckily, SW5e's techcasting system is all about a character pulling out and using technology they technically shouldn't have on them, but do anyway.
Just as a human techcaster can cast explosion and flavor it as them throwing a grenade, even if they have no grenades in their inventory, a Vong player should be able to cast acid splash and flavor it as them hurling some huun nerve gas, or their translation program being the use of the tizowyrm in their ear to translate what they hear and say. Most tech powers could reasonably be performed with Vong biots, so Vong techcasters could be treated as those who know the art of Shaping, a clever and simple way to incorporate Yuuzhan Vong biotechnology into your game.
Starting out
On the next page is a summary of the various castes among the Vong, to give an idea of what sort of Vong are the most heavily represented, what sorts are not, and why the differences between them might be very helpful for making your own character.
Just as you start a game as a low-level character, it may be easier to start out as a low-class Vong. A "normal" Vong, for lack of a better word. They are not as fanatical in their beliefs as their superiors, and are frequently oppressed by them, even forbidden by and large from exercising their faith in certain ways.
Weak, dissatisfied, less prone to xenophobia or technophobia, possibly even heretics; these are the sorts of Vong who more readily abandon their indoctrination in favor of a better way.
You could play as a terrifying crusader on a warpath against all droids and Jedi, mutilating yourself and your enemies to earn ever more honor in the eyes of your gods. But the best part is, you don't have to.
Castes
Warriors
When you think of a Yuuzhan Vong, you probably envision a bald, tall, black-armored fighter with an amphistaff and some sort of flaming, poisonous weaponry jutting out of their skin. This is a typical member of the Warrior caste, the zealots that mainly made up the invasion force in the war.
A fan of Star Wars or an in-universe citizen may very easily think most if not all Vong are like this, but the truth is they only ended up the way they are because they are brainwashed and conditioned from birth to be the perfect soldiers. Fearless, merciless, and suicidally unquestioning in their loyalty, these make for the perfect NPC enemies to fight, but maybe not the easiest of player characters to roleplay as.
Shapers
Another popular example is the Shaper caste, those who use secretive abilities to grow and manipulate Vong biotechnology, or conduct the grafting ceremonies that augment their warriors. They are the equivalent of scientists and engineers, and are honored as being especially close to their gods. In SW5e, they could be literal engineers, using their techcasting to fully emulate their abilities.
Priests
These Vong pull the strings of their society, electing a Supreme Overlord, speaking on behalf of the gods, and carrying out "purification" of those Vong who are caught using or being influenced by mechanical technology. They are equally if not more prone to having their bodies grafted as the Warriors.
Intendants
These are the politicians of the Vong, but they are a highly adaptable caste that also serve in more active roles. They are spies and scouts, caretakers to the creatures forged by the Shapers, and are the guiding hand of Yuuzhan Vong government. They are the smallest caste, below the Warriors and Priests in rank, and have a reputation for deviousness.
Workers
The lowest and largest caste, tasked with menial labor, the Workers are comprised of many different sorts. There are those who were once of higher castes by were cast down for failure or deformity. Others are simply born as Workers, and the caste also includes the slaves and Shamed Ones among their number. (Slaves are not even Yuuzhan Vong.) Regardless of their specific designation, all Workers are universally looked down on by the higher castes. Some are afforded token amounts of honor, but they did not enjoy the same benefits as the higher castes. All Vong are forbidden from intimacy with those outside their own castes, but such love affairs involving those of the Workers are considered especially depraved.
Shamed Ones
Despite the Workers including the Shamed Ones as a part of them, the Shamed Ones themselves truly have no caste. They are the heretics, the blasphemers, the deformed, those whose failure was ultimate, they whose bodies rejected implants grafted by the Shapers. They are seen as those the gods have turned their eyes away from, and thus do the Vong above them as well. While Workers were not allowed to have grafting ceremonies performed on them, the Shamed Ones were not permitted to attend any ceremonies or worship any gods other than Yun-Shuno, the Pardoner. Any step outside of these harsh constrictions of liberty is seen as an insult to the divine, for which punishment is swift and unhesitant.
Examples
Fallen from Grace
You were once a Yuuzhan Vong Warrior or Shaper. You had honor, you were feared and respected, and you were powerful. But, due to an unfortunate accident, you were dishonored, and cast out by your own people. Now a Shamed One, you seek to reclaim your former glory, to exact revenge on those who tossed you aside so easily or orchestrated your downfall.
If your dishonor was brought by being disfigured, you could say a grievous injury left you not as capable as you once were, explaining why you're now level 1. Another thing that could turn an elite into a Shamed One is if your body rejected a grafted implant, which could explain why you don't have any. Or, if you do, you could start with the Augmented Cyborg feat--likely as a Hermit--giving yourself an implant that serves as a harsh reminder of whence you came.
Blasphemer
Maybe you were different from the rest of the Yuuzhan Vong to begin with. Through a blasphemous interest in mechanical technology, or revolting relations with other species, you were cast out and branded a Shamed One. At this point, you decided you have no interest engaging in manual labor for your superiors, and abandoned the Vong, so you might find freedom to pursue the interests they deemed so reprehensible.
A character like this would have little to no ties to other Vong, and could be more willing than others of their kind to try out non-organic technology, perhaps even developing a liking for things like blasters, starships and droids. Depending on the nature of your blasphemy and exile, many backgrounds could make sense for this kind of character.
Lower Caste
You are simply a poor, downtrodden soul who has only ever known the barbarity of the Warriors or the judgment of the Priests. Regardless of the reasons why this is your life, you do not want it anymore, and a the earliest opportunity, you left it all behind, trusting your fate to the strange and mysterious new galaxy you find yourself in without ever looking back. The Servant background works well for this, as does Laborer, where your contact could be a Vong you keep in touch with.
Higher Caste
A Priest, Intendant, Warrior or Shaper would be difficult to begin a game as. It'd be akin to starting out as an Imperial Commander or a Jedi Master. However, depending on how a campaign goes, you could eventually become a member of these castes. You could start out as a level 1 novice of the caste, whose training and conditioning is not yet complete. Members of a caste are almost always born into them, so this would make sense. For campaigns beginning at higher levels, you would have more freedom to craft a character however you saw fit; into a battle-hardened Warrior as a fighter or berserker, a secretive Intendant as a scholar or operative, or a masterful Shaper as an engineer. Depending on your caste of choice, several backgrounds could be appropriate, such as Soldier, Noble, Scientist, or Investigator. These options also work well for one who is Fallen from Grace.
This example can be combined with the Post-War example, in which the caste system was abolished, but the titles of those castes and their implications remain the same. Meaning, these higher castes are no longer higher than others, and anyone could become one of them if they have the aptitude.
Praetorite
A military force in service to the Intendant caste. Before the war even began, for thousands of years, the Vong sent out scouts, spies, troops and engineers to help the main fleet secretly gain a foothold in the galaxy. Even in eras as far back as the Old Republic, you could play as a member of this vanguard expedition, seeking ways to map out and soften up the galaxy where possible, gathering information to deliver back to your masters, establishing bases of operation, even aiding your enemies in putting down threats that may pose a problem for the inevitable invasion. A spin on the Criminal or Pirate backgrounds would be well suited for a Praetorite.
Jeedai Heretic
Just because you can't use the Force doesn't mean it can't be a part of your life. The Jeedai Heresy is a religion that started toward the end of the war that subverted the teachings of the Priest caste. Rather than being a mysterious and demonic power, the Jeedai Heresy teaches that the Force is the final breath of the Yuuzhan Vong's creator god, and that the Jedi are angels sent to do his bidding from beyond.
If you play as a Jeedai Heretic, you would have a spiritual fascination with the Force and its users. You could venture out, seeking to be of aid to the Jedi, which could explain your friendship with a Jedi character in the same party as you. Even though you can't use the Force, you could seek to emulate a Jedi and carry out the will of the Force in your own way. And to take things a step further, you could take the Force Sensitive background feat--possibly from the Force Adept or even Jedi backgrounds--and become a true Jeedai yourself. This has precedent, like when a Shamed Shaper forged a link to the Force by grafting a piece of a yammosk into his brain, or when an unknown darksider Vong faced the Jedi after the war.
Post-War
After the Jeedai Heresy sparked a cultural revolution that aided in ending the war, the Yuuzhan Vong willingly exiled themselves to the Unknown Regions, on the living planet Zonama Sekot. Their caste system was abolished, and their fleets destroyed, but many of them still lived in the galaxy proper. In this new age, anything is possible, and all sorts of exceptional Yuuzhan Vong characters could appear, believing that they must evolve to survive--learning how to coexist with species traditionally regarded as weak or impure, and letting go of their own prejudices.
Examples of this in lore include a Master Shaper and her Warrior guards allying with the Jedi to heal and terraform worlds ravaged by the war. Another was a pirate who served aboard a vessel crewed by many different species, and taught a young human boy to be highly adept in the use of biots. Even still, there would remain Vong who cannot let go of the old ways, including a mad Shaper who joined the Sith and taught them his art for their own ends.
The rest of the galaxy would still be distrusting of the Vong in this era, but there would be no shortage of allies nonetheless. However, even after the war ended, Vong biotech was still outlawed by most governments, making it a popular product on the black market. A Vong character, especially a Shaper, would find themselves in an advantageous position in this sort of economy, with their skills and expertise in high demand by unlikely potential customers. The Far Traveler background works well for most Vong, but especially so for this.
