The opposition of light and darkness is a false dichotomy. Light is a positive presence, but it is not opposed by darkness. Rather, darkness is but an absence of light. Put another way, darkness, as most understand it, does not—and by definition, cannot—exist.
But light is opposed by something. The ignorant model of light and darkness places light on the positive end of a spectrum and darkness on the negative. To correct this model, one must instead place darkness in the exact center of the spectrum, neither positive nor negative. Beyond this neutral point, one enters the realm of mvadha.
Mvadha goes by several names: anti-light, dark matter, et al. The term mvadha comes from the Nacdrel, one of the few cultures in which this “negative light” is both known and more than just an obscure bit of jargon. The term is derived from the augmentative form of the Nactlylvh word for darkness, literally translating to “great darkness”.
Mvadha is similar to light in most respects; it travels at similar speeds, reflects off surfaces, and refracts through non-opaque substances. However, mvadha is far rarer. While light sources tend to be fairly constant (the sun, the moon, fire, etc.), mvadha sources are virtually unknown. Where mvadha does naturally occur, it is bound by magic in ways that make it impossible to ascertain its natural qualities.
In cases where the binding magic is dispelled, the mvadha and the surrounding light destroy each other. Although it may seem that only the mvadha is destroyed, this is not the case; light only seems to persist because its source (often the sun) constantly renews it.
Theoretically, if a constant mvadha source was ever set up near an equivalent source of light, the resulting environment would appear perfectly dark; the light and the mvadha would cancel each other out. Incidentally, to most mortals, this would give the appearance that the mvadha had won. This is because most creatures are incapable of seeing mvadha. A region “lit” only by mvadha would appear black, indistinguishable from neutral darkness.
Nacdrel claim to be able to see mvadha in the same way that most beings see light. However, their attempts at description have proven impossible to interpret.
While mvadha’s natural state is poorly understood, its magical state is well-documented. Mvadha may be infused with soul energy to bind it in certain forms. Not many beings are capable of this, however. Nacdrel are the most common examples, but there are also the Drae and the Ynds. The obvious connection between these beings is that they all have strong connections to themes of death or darkness.
In this case, mvadha behaves much like a physical substance. Water, for instance, may take the form of ice when robbed of all thermal energy, while an infusion of thermal energy turns it to steam. Likewise, the addition and subtraction of soul energy alters mvadha’s state—albeit in an opposite way. Higher amounts of soul energy result in solid mvadha, while lesser amounts result in a gaseous. The same, of course, can be done with light, and experiments in the magical binding of light have led to the development of many theories on the nature of mvadha.
Most of the world’s direct studies of mvadha have come courtesy of the Nacdrel, whose most striking biological quirk is that their physical bodies seem to be made of mvadha. The reigning theory is that Nacdrel souls produce such powerful auras of soul energy that the mvadha surrounding them is held in stasis throughout their lives. Where this initial mvadha comes from, no one knows. But when a Nacdrel dies (death defined, of course, as the departure of the soul), the absence of soul energy allows the mvadha to return to its natural state and, consequently, destroy and be destroyed by any surrounding light.
Thin pieces of magically solidified mvadha appear translucent, like dark, unreflective crystals. As thickness increases, the mvadha becomes utterly black. Most eyes cannot ascertain its three-dimensional form due to its lack of reflectivity; it appears as a bizarre, two-dimensional cutout.
Liquid mvadha displays the same variation in appearance from translucent to opaque. In behavior, the liquid mvadha is much like liquid mercury.
Mvadha’s gaseous form is similar to a black, oily smoke. Some have compared its behavior to that of ink dropped into water.
Regardless of its state, magically bound mvadha is described as “frighteningly cold” to the touch. In rare but extreme cases, those who touch it are stricken with instant frostbite. However, as light has no temperature, it is assumed that mvadha is the same, and therefore that the cold is an effect of the magical binding.
Another odd phenomena is observed when mvadha is unbound: a sense of fear. Reports are few and far between, most often coming from those who were close at hand upon the death of a Nacdrel. The initial feeling is infinitesimally brief, but the memory of it leaves a lingering terror. It has been speculated that this is the result of unbound mvadha, in its natural state, striking or passing through the observer before being destroyed.