TR,DL: An Aboleth Slave is the product of an unlucky individual who has been enslaved by an aboleth. A slave's life in the Aboleth s' hands is a miserable one that most servitors can't escape from. Particularly, an Aboleth Veteran Slave is a creature under the control of its Master that has lost the will to fight for its freedom.

Popular stories about Aboleths in sailor towns are often told to young people to warn them about the dangers of the sea. " Always dock your ships before it gets dark, no matter how tempting the plunder may seem to you, or an Aboleth may come and take you deep into the ocean, where it will force you to become its slaves". Young people very often laugh, assuming that it is just an old legend. And instead the crazy sailors may be right.

Lurking in the deep (or maybe in your local lake, who knows) there are Aboleths with a dozen, or if they are quite high on the social ladder, a hundred slaves who work hard to fulfill the desires of their Master. These are creatures unlucky enough to have encountered a live aboleth and have fallen under his mind-dominating abilities. Becoming an Aboleth slave is considered by many a fate worse than death.

Life as slaves of an aboleth is not easy at all. First of all the Aboleths often enjoy tormenting their slaves in moments of pure sadism with images from their past life, tormenting them then on the fact that now their only way is to serve their Masters until their death. "Look at your past life: how pathetic it was! Now that you’re under my control, you finally have a purpose worthy of your life of a lesser being, and that's to crawling under my tail" -Phenorr, an aboleth slavetaker.

Secondly, many slaves undergo a transformation by their Master. The Aboleth covers the designated slave with its secretions to infect the slave with the Aboleth Disease. In a short time the slave finds itself covered by a transparent and slimy membrane and obtains fins and gills. Fortunately for the Aboleth, he gets a new slave capable of breathing both water and air. Unfortunately for the victim, if their skin is not submerged in water, in little time the new skin begins to burn causing great pain to the slave. Some slaves were found burned on dry land for spending too much time without getting wet, probably to follow an irrational order of their master.

Finally, under the mental domination of the Aboleth a slave no longer has the ability to think for himself. The slave becomes a pawn in the schemes of his Master, following every order of the Aboleth to the letter, although often these orders are fatal. Their psionic domination makes them extremely loyal to their master, so much so that they consider him a deity and consider their slavery a gift of destiny. However these feelings are not shared by the Aboleth. Aboleths are schemers who think of their plan in the far future, so they see the lives of their slaves as expendable, Besides, what difference does it make in a thousand years if a particular slave is crushed by a boulder while tunneling for the Aboleth?

It’s important to specify that, under the command of the Aboleth, a hierarchy of slaves is established. If there are few slaves in the community then they are all categorized into one caste. If the Aboleth has many slaves, they are divided into several categories:
Viknos (Experiment): Slaves of this category are part of the lowest category in the hierarchy of servants are often used by their Master for cruel and often fatal experiments. In fact, very often the Aboleths do experiments on other creatures to try to find the perfect slave who is strong, able to best fulfill the will of the Aboleth and who is faithful to his Master. The Aboleth in fact through these experiments have managed to create formidable slaves, such as deep scions, sea spawns and (surely their most successful creation) skums.
Uungorr (Mule): these are the basic level slaves. They are used for the construction of infrastructure and in general works where only muscles are needed. It’s the class with more slaves in it and they’re all interchangeable. In the event of a lack of labor power (because perhaps the slave managed to free himself from domination or because the aboleth wanted a snack that morning) other slaves of higher castes can be "degraded" to this category. In this category there are usually: Humans, Trolls, various beasts, Goblins, Dwarfs, sea spawns etc.
Nosorr (Warriors): these are the warriors of the Aboleth. They can usually be guards who attack all those who want to enter their master’s lair (yes, even their old friends and lifelong companions) or, more rarely, an army ready for war (in case an Aboleth has entered some war) ready to terrorize enemies to show the strength of their master.
Usually in this category there are: skums, strong beasts, constructs, orcs, barbarians etc.
Jookul (spies): Spies have a particular role among the slaves of the aboleth. In fact these only the eyes of their master on the mainland and therefore very often these slaves are not transformed but their mental domination is reinforced (if the Aboleth can somehow) since every time a creature moves away from the aboleth for more than a mile the slave could come to his senses. Creatures in this category are creatures that one would not expect to be under the control of the aboleth, such as: deep scions, rouges, doppelganger, shifters etc.
Yngthoonath (entertainers): This is a category that only the most powerful Aboleths can afford. Once they are enslaved to creatures that the Aboleth considers particularly amusing, he forces them to perform in often strange and unusual shows. Sometimes these performances can depict important moments in the life of the Aboleth’s ancestors or show the power and greatness of the Aboleths over other creatures. Although this seems to be the "luckiest" of all classes, it must also be said that if the Aboleth doesn’t like a performance, he could eat or kill slaves in a fit of rage. Some examples of creatures in this category are: galdiators, circus performers, menestrels, wizards ecc.
Phenkuligos (Clerics): Aboleths are known to hate any form of deity, but they, considering themselves superior to other creatures, do not mind being treated as a god. That’s why among the slaves of an Aboleth, there are priests and clerics. Their function is to honor their master through sacrifices (sometimes with slaves themselves) and continual worship. Of all the slaves these are the most devoted to their Master and would be willing to do anything to defend him. The luckiest receive the "honor" of becoming bearers of their Master’s will to all the uncultivated masses, in the hope of finding some worshipper among the crowds. Among the slaves in this category we can find: Clerics, Druids, priests etc.
Dethnevikath (Protected): This class is particular. In fact this is considered the "best" class by an Aboleth. In fact in this category there are all the most important slaves of the Aboleth. It is important to know that often among Aboleth there are competitions to see who has the strongest and most beautiful slaves (although one may consider "beautiful" the vision of a slave with slimy skin). Not to say that the Aboleth cares about these slaves, of course not, but consider the lives of these slaves a priority over that of others. Some slaves in this category are: powerful sorcerers, aboleth’s warlocks, demons, heads of big cities, Aboleth slave veterans etc.
P.S: Not every Aboleth that has a lot of slaves has all these categories, and maybe there are more categorie that are unknown to us, but according to recent studies this seems to be the norm.

 With all of that said, can an aboleth slave escape its terrible destiny? Well...kinda. Normally the magic enslaving other creatures to an Aboleth is quite strong, but if a creature has fallen under psychic domination there's still three opportunities of freeing themselves. Firstly, as we said before, a slave can regain his consciousness if it's more than a mile from the aboleth and it can try to free his will once a day. Two problems with this. The first one is that freeing themselves from the Aboleth's domination is as difficoult as the first time, and the other one is that (as you've might have guessed) Aboleths are incredibly intelligent. So when they'll send a slave to do something outside that mile's radious, he will do whatever possible to lower a slave's chances to escape. (such as using a collar of obedience). Pretty difficoult for a slave to escape if they're send to do something for an Aboleth, huh?

Still there's another two options to escape. Every time an enslaved creature gets hit the telepathic link to its master gets weaker, allowing a chance to escape. But again, Aboleths are super-duper ingenious and they'll do everything to prevent their slaves from hitting themself. And when their slaves will attack another creature(s) the aboleth will try to command them to take as little damage as possible. So another unlikely route.

The last method a slave can use to escape from its master it's death, the aboleth's death to be exact. But how can a single, powerless slave defeat an aboleth, moreso if it's under his control? Maybe some powerful adventurers can come and free them, but that's leaving it to chance. Maybe the adventurers have to kill the slave because it's protecting the Aboleth or because it sacrificed to leaving its Master unharmed. And even if they manage to kill the aboleth (without killing the slave itself), the Aboleth doesen't truly die... it just respawns from the Plane of Water, giving it another chance to re-enslave the servitor! 

And all of this is without counting that Aboleths in the years that they've spent playing around with other creatures have developed a way to grow their mental dominations' powers letting them permanently keeping control of their slaves! But for this to happen, the other creature needs to "agree" about having its will eradicated. This usually happens if the slave has losed its will to fight for its freedom completely, usually after all of the physiological torture that the slave is subjected to and after having realized that it's almost impossible to escape an Aboleth mental domination, abbandoning itself to a life of dirty slavery for a terrible and cruel master.

At this point the Aboleth (able to know the creature inner thoughts because of the telepathic link) takes the slave and performs a terrifying and painful ritual that can only be done if both parties "agree" to the transformation. This ritual alters the body and mind of the slave, destroying all of its past life and almost all of its Intelligence in the process. The creature also loses all physical traits of their former race transforming in the ideal aboleth slave and becomes to enjoy its slavery, seeing the Aboleth as the one who gave him purpose in life. For such individuals, no spells, no regaining their conscousness, nothing can be done to free him for the shackles of the Aboleth's enslaving. Even the death of its Master can't free it, because the slave is so deeply connected to the Aboleth that every time the Aboleth returnes from the Plane of Water the slave is compelled to return to its Master and serve its will. Funnily enough a slave that is forever subjugated to its Master is called by it a Veteran Slave and it's considered by the Aboleths the most perfect form a creature (that isn't the Aboleth) can reach and every creature should aspire to become a Veteran Slave to serve the Aboleths.

Because of this, the few aboleths powerful enough to have a veteran slave wiew this servitor as their most prized slave not because of their strength, but because they are a testiment that their mental domination powers are so incredible that they make a creature give up its freedom and desires (almost) willingly only for the pleasure of the Aboleth. The Veteran Slave is trurly the most miserable slave of them all because it's hopeless.

Ok, even with this difficoult circumstances, let's imagine that a slave is succesful at escaping. What will it do now? After all, it spent only the Aboleth knows how many years under its control. Will he search for the protection of another master, possibly an aboleth? What about it's mental state, after all the poor soul was tormented all the time when it was captive. Will he try to fit in their previous society? I mean, it's unlikely, seeing that he's now a slimy monster that one could think appared from a dark-twisted fable. Will he live a life of solitary confiment? Maybe, but he has so many needs now, primarly the needing of staying wet as much as possible, if not it will die. Maybe, just maybe, the slave might find a cure to its disease and live happily forever. Extremely unlikely, but non impossible. You see know how many problems does the aboleth's capacity to enslave and transformer others bring?

So, next time you laugh at some old and crazy sailor's story regarding an Aboleth, think twice. You might just be the next Aboleth Slave in a line of never ending slaves.

Thank you for reading this far! I don't know if this creature can be quite unbalanced in a real game setting because it's my first time doing something like this and I haven't actually learnt all of the basic mechanics, so pardon me if something here is extremely unbalanced. Now this was a passion "project" of mine, because I really like the Lovecraftian horror that these creatures can provide, especially for the treatment of their mental dominated slaves. And after some research, I was interested in writing a sort of ecology of the aboleth slave and the terrifying thought of being under the mental domination of a creature that considers you nothing more than a expendable tool. So that's why this description is so long!