Terminology

Aether:
Aether is what the Legendborn call magic, but different practitioners of magic call it different things. Magic or aether, is also known as “Root” to Rootcrafters.

Camlann:
Camlann is a massive reckoning. When the Shadowborn grow restless and powerful every few centuries, the Legendborn are made aware through the Awakening of their knights. The more danger there is, the more knights are Called, and the closer they are to Camlann. When Arthur is Awakened, then Camlann has come, and there is an epic battle against the Shadowborn on the horizon. The last Camlann took place during the American Revolutionary War, and contributed to it’s scope.

The Order:
The Order is short for the Order of the Round Table, from the tale of The Legend of Arthur. If you aren’t familiar with the likes of Lancelot, Excalibur, Merlin, Camelot, Morgana, and the like. It’s probably best to acquaint  yourself with a basic understanding of Arthurian Myth before reading this book, as this book is a modern retelling of that story. The Order has been around since the 6th century, since the time of Arthur and the Knights of the Round Table. Their mission is to hunt and kill the Shadowborn.

The Sight:
The Sight is what allows the Order to see Shadowborn. Regular people (Onceborns) cannot see, hear, touch, or interact with the Shadowborn in any way. At least not when the Shadowborn aren’t fully corporeal. The Sight allows the Order to perceive the Shadowborn so they can dispose of them before they are fully corporeal and can terrorize people.

Legendborn:
A Legendborn is the highest-ranking member of the Order of the Round Table. They are either Scions or Squires, and are the only people in the Order allowed to recruit new members to the cause. The Legendborn and the Order exist to hunt and kill Shadowborn that seek to hurt people.

Onceborn:
Onceborns are regular human people without the Sight. They go about their everyday lives without knowing that demons and magic exist.

Shadowborn:
Shadowborns are demons, and there are many subspecies. They cannot become fully corporeal easily, but the more aether they consume, the more corporeal and powerful they become. They can only access the human world through Gates made through magic from our dimension to their hell realm.

Rootcraft:
Rootcraft is a balanced form of magic. It involves borrowing power from one’s ancestors through offerings to said ancestors. It is nowhere as near powerful as the magic used by the Legendborn, but is far less dangerous, and won’t take a toll on the caster in the same way. All magic demands a price. Rootcrafters pay it with offerings, which seems to allow them to live long, happy lives.

Bloodcraft:
Bloodcrafters are considerably more powerful than Rootcrafters. Bloodcraft is a form of magic that involves taking aether/root/magic/etc. from the world and tying it to yourself and your bloodline (hence the term Bloodcraft) without a payment of equal weight. Magic requires payment though, and it usually takes it by shortening a Bloodcrafter's lifespan considerably. For example, the Spell of Eternity that Merlin used to imbue the knights' abilities into their descendants would cut off their life spans, to the point where most didn't live past the age of thirty-five (more details later).

Scions:
There are hundreds of living descendants of the knights of the Round Table, but the heir to the knight's Line between the ages of 16-22 years is called a Scion. If a Scion dies, the power of their respective knight is passed down to the next heir (their next eligible relative: child, child's child, sibling, sibling's child, etc. It's a lot like British succession). However, to have their knight's powers and abilities, the Scion must be Called by their knight, at which point they are then considered Awakened Scions. An Awakened Scion is imbued with the specific unique abilities and qualities of the knight whose Line they belong to, including an affinity for aether (which all Awakened Scions have). For example, the Awakened Scion of Tristan will have the abilities of marksmanship and speed, along with an aether affinity. Otherwise, they are just adept demon hunters. Scions can can can conjure aether weapons and armour at a momemt's notice for themselves their Squire in the midst of battle. The knights are Awakened in order from lowest to highest rank. Meaning the twelfth-ranked knight of the Round Table, Sir Galahad, is Awakened first, then the eleventh, then the tenth, and so on. Until the last knight, Lancelot, is Awakened, then finally, the Scion of Arthur is Called. Usually, no more than eight Scions are Awakened at a time. The more knights are Awakened, the more danger there is, and the closer Camlann is. The fifth-ranked Scion (Scion of Kay) hasn't been Called for over fifty years. The Spell of Eternity that Merlin cast allows the knights' descendants to inherit their unique abilities, however, because it is Bloodcraft, it comes at a cost: the Abatement. The longer a Scion -- and consequently their Squire -- is Awake, the more it drains them. After they age out (are older than 22) most don't live past thirty-five. This is why the Legendborn are so revered.

Squires:
Every Scion has a Squire. A Squire is essentially the Scion's partner in battle and protector. Scions and Squires are bonded by the Warrior's Oath, which allows them to know if the other is in danger, and feel each other's emotions. Squires are only bonded to their Scion after they have been Called. The Warrior's Oath also allows the Squire to access the abilities of the knight their Scion is descended from. The Squire’s job is to protect their Scion forever, even after the eligibility period is over and the inheritance disappears. They share an intimate connection through their bond. Sometimes it’s romantic, but often it’s not. Because the Scion and Squire are bonded, Abatement will affect the Squire as well.

Pages:
Pages are young teenagers that compete in trials for Squire positions. Each Page must have a Legendborn sponsor, as they are the only ones allowed to recruit new members. Through these trials, Pages are eliminated to narrow down the choice at the Selection Gala, where Scions in need of a Squire will Select a Page to be their Squire. Sometimes, the Page makes it known which Scion that are hoping to Squire for from the beginning of the competition. The Pages that fail the trials are still allowed to attend Order events, but they don’t have anywhere near the same privileges or power as Squires. Pages are almost always children of Vassals.

Vassals:
A Vassal is someone outside the Order that knows of it, but not of the entire extent. Vassals do not have the Sight, so they can't see aether, or the Shadowborn. However, they are sworn to the Code of Secrecy and pledged to the Order. They serve a certain Line, and their children can be sponsored by a member of the Line they serve. Vassals can police officers, politicians, doctors, university deans, multi-million-dollar CEOs, and the like. They are people that the Order can benefit from being affiliated with. In return, Vassals gain more money and power. Vassals usually serve as an extended network to allow the Order to keep tabs on Shadowborn and any other otherworldly anomalies. They also help ensure that Onceborns don’t become aware of the Shadowborn and go into a panic. Vassals are often wealthy, powerful, and prestigious white old-money families that have served the Order for centuries. Most Vassal children become Pages and oftentimes Squires.

Merlins:
Merlin is a title, not a person. Merlins are sorcerers that serve as mages for the Order. They have a powerful affinity for aether, can mesmer people (mind control/memory manipulation) and can create constructs (physical objects, animals, etc.). Merlins are also far stronger, faster, more agile, have better senses, etc. than typical people or Scions that are not yet Awakened. Merlins also have unnatural eye color; for example, Selwyn Kane, the current Kingsmage, has yellow eyes. There is one Merlin for every chapter of the Order. Kingsmages are also Merlins. Merlins are part-Shadowborn. Sometimes, a sub-species of Shadowborn (succubi) will have children with a human. The result is a Merlin. If a Merlin has a child with a human, their child would be as much a Merlin as they are. The bloodline isn’t diluted. In fact, a Merlin’s parentage doesn’t seem to affect how powerful a Merlin is or isn’t. Merlin children are essentially human at birth. When they turn seven, the changes (speed, strength, senses, etc.) start, and each year after that, Merlins become more powerful and have a stronger connection to aether. But each year, they also lose a bit more of their humanity. It is called "succumbing to the blood." When Merlin created the Spell of Eternity for Arthur and his knights, he created a similar one for himself. His descendants would inherit the unique mage abilities he had honed over time: mesmer, constructs, and an affinity for aether. However, Merlin knew that part-demons would never help the Order, so he added insurance to his spell; because the darkness of the underworld and the light of the living shouldn't exist in one body, a Merlin's blood fights itself every day. The older they get, the stronger the demon essence becomes, but their commitments to the Order and its members keep them from going over. The Oaths that a Merlin swears bind the two sides of them together, keeping them in control of their souls as long as they are in service. It is why Merlins are Oathed early, before their blood can gain a foothold. That is also why the worst punishment for any Merlin would be being cast out of the Order's service.

Kingsmage:
"Only the most powerful Merlin child in a generation is Selected to take the Kingsmage Oath. The child is taken from their family and bound here, in a formal ceremony before the chapter, to a child Scion of Arthur. For the rest of that Merlins's life, they are the Scion's sworn protector until death."

Morgaine:
Morgaine is a title, not a person. The Line of Morgaine is a group of rogue Merlins, from before they were Oathed. Essentially, they are mages that abandoned the Order because they didn't agree with the Regents' way of doing things. Some stories say they started attacking Order members, and using mesmers on Lieges to influence the Lines and Vassals before they officially splintered off and renamed themselves. After the Shadowborn, the Morgaines are considered the Order's number one enemy. The Morgaines are the primary reason the Regents have a zero tolerance policy for anyone using aether outside their purview. From the little we know about dark magic, it seems to involve the Shadowborn. So far, it looks like the Line of Morgaine work with the Shadowborn. It’s also possible that the Shadowborn serve the Line of Morgaine. Morgaines are not nearly as powerful as Merlins because they lost access to the training and ancient texts Merlins use to develop their abilities.

Lieges:
Lieges are former Scions and Squires. Due to this, they are adept in battle, and have more experience than the current Scions and Squires. They don’t have access to the powers of an Awakened knight, though. Some Lieges were Awakened during their time as Scions or Squire, and others were not.

Indigenous people living in North Carolina that were practitioners called aether or root they called it spirit. They fought demons and other magical beings. And sometimes had children with demons and other magical beings