Dark
A dark is a mechanism of dream magic that associates a particular event or object with a particular magical result. In celemological terms, a dark can be considered a sort of a persistent, fixed, non-finite sparked enchantment. Some celemologists do not consider darks to technically be enchantments, but rather a part of the fundamental infrastructure of dream magic through which enchantments are created. Others consider darks to be the only true enchantments of dream magic, all other lasting magical effects "pseudoenchantments" that are their mere consectaries. In the end, though, the relation of darks to enchantment is only a matter of definition and semantics.
While some darks are singular affairs that hold only in local areas, most darks fall into particular categories, and are created according to some mechanisms that are, if not necessarily simple, at least simpler than creating a new unrelated dark from scratch. The existence of these categories of dark is not due to any inherent properties of dream magic ab initio; rather, it is because these categories are themselves defined by greater darks. These superordinate darks, called "bare darks", tend to be designed in such a way to facilitate the creation of lesser darks of a specific nature. Due to the difficulty of creating bare darks, and the power necessary to do so, few such darks exist, but those that do have come to be themselves considered fundamental parts of the structure of dream magic itself. Dependent darks created through bare darks, including spells, geasa, and others, are collectively called neighbor darks, while independent darks that are neither bare darks nor neighbor darks are called halo darks. Neither of these terms, however, is in particularly common use, and certainly neither is heard as much as "bare dark".
While darks can be created locally, establishing their associations only in a limited (though possibly very large) area, it is also possible to create a dark that applies throughout all Gomara. Most such universal darks are bare darks, while conversely most halo darks are local, but there are a handful of universal halo darks, though they're not well known.
The study of darks is called œacology.
Etymology
It's often said that the word "dark" comes from the fact that most people don't really understand how these magics work; they are "dark" in the sense of secret or mysterious. Others explain that the word is a corruption of "derrick", a term given to represent the important röle darks play in making up the ultimate scaffolding of the arcanum. Another popular derivation traces the word to the Sanskrit दारक, daaraka, meaning "child", the rationale being that a dark is a figurative child of magic itself. Less prevalent but still sometimes heard supposed sources include the Uzbek dahar, meaning news; Slovak darca, meaning donor; and even the Woiwurrung dharrak, meaning arm.
All of these, however, are folk etymologies. "Dark" is indeed a corrupted form, but not of "derrick" or any other English word. Rather, it comes from the Calorran daraco, meaning style or manner of use. Indeed, the still standard adjective meaning related to darks, "daracic", still hearkens back to The concept behind the name is that darks are created as specific ways of using dream magic, as higher-level methods provided to work effects more efficiently without having to manipulate magic at the most basic level... that they are, therefore, specific ways of using dream magic.
Bare darks
The following are some darks that have been established throughout Gomara. While there may be other bare darks created over limited scope, or even other estre-wide bare darks that are little known, the darks listed here have come to be considered fundamental parts of the structure of magic itself.
Spells
Spells themselves, while now often taken for granted as an essential part of dream magic, owe their existence to a bare dark. Possibly one of the first bare darks created, or in any case almost certainly formed not long after Gomar the Ancient first brought magic to the worlds (and according to many stories created by Gomar Himself, though many scholars doubt that), the dark that enables dream mages to cast their spells has certainly had a profound effect on the estre.
There's some question, in fact, as to whether the spells of dream magic really owe their existence to a single bare dark. Some celemologists hold that each path of dream magic, as classified in standard carminical taxonomy, is brought about through an entirely separate and independent dark. This has always been a controversial theory; even if evidence has mounted that several paths were created independently of any now-extant path, many celemologists hold that all these paths were still created through a single now-lost "ur-path" that predated even the so-called "First Path" of Legera. Even if this is true, many celemologists still maintain that it makes sense to regard these other paths as bare darks in their own right, even if they were created through another bare dark, and some celemologists go so far as to say the same of circles and some lower taxa, in extreme cases down to motive. At this point, however, this perhaps becomes a question more of the definition of "bare dark" than of the real properties of the carminical taxa, and more of semantics than of celemology.
Geasa
Another fundamental dark known and used over most of Gomara is the geis, through which a determination to pursue a particular course of action—or eschew specific actions—brings with it beneficial consequences. However, if the geis is broken—if the prescribed course is not followed, or the proscribed action is performed—then the geis brings down upon the geiseach (the person under the geis) punitions much more severe than the rewards they would have accrued from keeping it.
There are some geasa that are well known and commonly used across many worlds. The Floral Geas, the Geas of Peace, and the Pauper's Geas are particularly widespread, presumably because they have relatively simple (though perhaps onerous) terms that have little reliance on any specific culture or ecosystem. Others are known and used only on single worlds, or perhaps small collections of worlds. Still others may not be commonly used, but because of circumstances or historical accidents have had an impact that spans many worlds anyway—an example of this is Xin's Geas, to which all the members of the powerful organization called the Xinunium are subject.
Pales
A pale is a region subject to a rhegus that, among other possible effects, grants one specific individual (the master of the pale) dominion over some of the pale's features and properties. Depending on the nature of the pale, this dominion may be exercised consciously or subconsciously, or some combination of the two.
Not all of Gomara is divided into pales; indeed, many worlddisks of Charos lack pales entirely. On the other hand, on many worlds the entire land surface, or even the entire surface, seas included, is divided up into pales.
Curels
Curels, or vocational darks, pertain to particular paths or professions that people can practice and pursue, and as they do they will find their abilities and skills magically augmented—or be granted new magical powers related to these pursuits. Curels have some similarity to geasa, in that both involve making a commitment in exchange for some benefits in return, but they differ in that the benefits to the curel can increase over time, and in that the practitioner of a curel generally incurs no penalty for leaving it. Indeed, many curels require no ongoing commitment past the initial embarcation; one's powers in the curel may not advance if one does not practice it, but one does not lose the powers one has already achieved.
As with geasa and pales, the commonality of curels varies from world to world, and perhaps from land to land within a world. In some places, curels are so widespread that everyone, or at least every adult, is expected to have one—or perhaps more than one; there is not necessarily any restriction on pursuing multiple curels, beyond the concomitant division of one's attention (though in most places learning more than one curel is uncommon at best). In other places, however, curels are entirely unknown.
Fasures
Fasures are something of a metacelemic dark; they do nothing by themselves, but can have effects combined with other darks, particularly spells. Essentially, a fasure is a (neighbor) dark associated with a particular shape. Many spells, and some other types of dark, can take a fasure as a parameter, which will affect some aspects of the magic depending on the particular fasure. Conversely, certain circumstances can "call" the fasures, leading to otherwise inexplicable instances of things appearing in or forming into the associated shape.
Names
Another dark well known on some worlds and unknown on others is that of names—in dream magic, thanks to this dark, names have power; knowing the name of a person or object facilitates certain powers over it. However, there is more than one kind of name. The name an object or person is most commonly referred to is the "use name", which may or may not be the same as the "deep name", the first name the creature or object was given after its birth or creation. Deep names are much more powerful than use names, and on worlds where the power of names is well known and widely used, people's deep names are generally kept secret; on worlds where the power is unknown or very rarely used, deep names and use names may be one and the same, since there's little value attached to hiding names.
Aside from the deep name and the use name, epeinologists—those who study names, in the daracic sense, not to be confused with onomatologists who study names in the more general sense—define several other classes of names with daracic significance: the high name, self-bestowed to augment one's power, but very dangerous if it becomes known by others; the key name, likewise kept secret but bestowed on a valued possession rather than oneself; the false name, a difficult to arrange name by which one may be referred without ceding any power; the joint name, which refers collectively to more than one entity; the switch name, a name corresponding to a particular identity of a creature or object that has several; the divine name, bestowed by a god or another being of great power; the deed name, a name usually granted after some famed accomplishment that gives the named being power rather than giving others power over it. Some even speak of a true name, a name given by magic itself, but it's uncertain that such a thing really exists.
Other darks
As already noted, most halo darks are local, and even many universal halo darks are not widely known. There are, however, some halo darks that have come to have a large impact on magical practices on many worlds. Shards, objects enchanted to in a sense contain a part of the enchanting mage's mind or soul, exist and can be readily created thanks to a universal dark. The same goes for tokens, talismans of a sort that can absorb ambient magic and augment a wizard's power, so long as they are not too numerous. Some celemologists maintain that the gods themselves owe their existence and abilities to a powerful dark.
Creating new darks
The method of creating new neighbor darks depends on the particular bare dark they pertain to, but is generally a relatively simple task, at least in comparison to creating new bare or halo darks. But creating other darks is not a task for a novice mage; it can be roughly likened to altering the "source code" of magic itself. Creating a new dark involves somehow interfacing with the basic nature of magic, searching it for aspects related to what one wants the dark to bring about, and then modifying it in just the right ways, guided by subtle reflections of the alterations effected. One can somewhat simplify the process and still end up with a working local dark, but to create a universal dark requires a great deal of work and care.
There have been several attempts to try to streamline the process of creating a dark, either by trying to break down the process into some sort of reproducible and reliable step-by-step algorithm of sorts, or by creating a dark that itself facilitates the creation of other darks. None of these attempts has borne notable fruit—unless one believes the story that just such a dark was created long ago, and all those who have created darks since have used this dark whether they were consciously aware of it or not, and that creating darks used to be even more difficult than it is now. Few œacologists, however, take this tale particularly seriously.