Since the Middle Ages, magic in the popular western mind has been associated with the ‘Black Arts’ and with that which is forbidden and condemned by religion. The association of the color black with material reality in both its subjection to destruction and perhaps its sensuous impurity seems to be universal amongst human cultures, but an association of black with evil and with death seems to be most emphasized in western culture; in China it is white that is associated with death (and death’s purity) and black that is associated with life and fertility, which although sensual and real rather than ideal (impure) are regarded as largely beneficial. The confusion of these semantic correlations with ethical and moral ones has wrought great confusion in the development of magical terminology, but this confusion can mostly be blamed upon religious belief structures. Hence, it is not in fact inappropriate to regard black magic an inherently anti-religious, although this by no means necessitates that it be regarded as ‘evil.’ Black magic, as an art, consists of the use of what are called the Dark Ethers. Its power dwells in the channeling of chaotic force, similar to the premise in certain interpretations of chaos magic that the ‘chaos’ is a definable tendency that manifests in ethereal patterns. Though occasionally difficult to distinguish from Necromancy (as defined in modern practice and on The Library of Knowledge), the Dark Ethers can be understood best as the focus of negative energy and, to put a slightly scientific spin on things, as Entropy. Entropy here being defined as the tendency of an energy system toward inertness through the breakdown of organized structure and pattern. The black essences are the power of negativity congealed and put to work by the focused practitioner of Black Magic. Notice this does not mean that Black Magic can have no creative application, but rather that its effect on things is a hastening of the natural breakdown/decay referred to as Entropy. Thus it is the opposite of the integrative function of White Magic - which is not strictly creative (consider cancer which is growth run wild).
When a novice magician becomes angry they are often fuelled enough to cast a spell in the heat of the moment which leads to the destruction of their target, hence the tales that are often told afterwards of a magician being so furious that a person's life was brought to ruin. Accounts of magics fuelled by hatred and negative passions are the essence of Black Magic, and the basis of the use of the Dark Ethers. This emotional firebrand is the means through which many magicians find their release. It is a way, in psychological terms, to vent themselves in a meaningful way. Unlike other venting techniques, though, these power manifest in the form of destruction on a target or targets. They can be used to influence the mind of a sentient target through inundation, to destroy the animate or inanimate target by inducing a concentrated charge of entropic force, or simply as any other energy to manipulate things around them in a more subtle way. The old saying "The best defense is a good offence" is the rally cry of the black magician, and their methods often revolve around this philosophy due to the proactive nature of the dark energies. The ease of influencing and controlling dark ethers through the use of hostile emotions does not mean, of course, that this is the only way such effects can be accomplished. Ultimately, it is an orientation toward negativity that is the black magician’s source of power, and thus, the cold fury of ruthless concentration or even the detached callousness of a dispassionate predator can accomplish equivalent results, although the tendency of most people to be capable of utter malice only when emotionally aroused makes intense passion a popular method.
By channeling their own spite, hate, anger, or even a simple will for destruction (which may or may not carry the previously mentioned emotional baggage) into a sentient target, the black magician actually has a curious ability to replicate these feelings in a human target with results somewhat reminiscent of demonic oppression. This ability to recreate spite, or any other variant of bitter feeling, can leave the black magician in a very good position. By eliminating the competition, black magicians can often seize rare and unique opportunities that would pass by the average person. Much like the politician who wins office by default, due to all other candidates dropping out or other such disqualifications, the black mage can truly seize the day and tactfully maneuver hirself into advantageous situations. Such a skill is undoubtedly the reason this art will never die out, and a defining ability within this caste.
Turning to non-sentient targets, the black mage remains undaunted, not needing to balk at many of the trivial things which bother the average person due to a keen sense of bringing a quick end to the discomforts of life. Enhancing the decay process of obstacles or using other variables under their control to crush adversity, even the smallest things in life bend to this overwhelming power. The specifics of where this power is usually applied remain foggy due to the different needs of the individual, but the point remains that, for a black mage, the issue is not a matter of "what shall I do?" but rather "what shall I target next?".
In this caste, more so than many others, Ripple Effect is something to be mindful of. Like throwing a rock into a pond, a disciple of this art must be wary of what they target and how powerfully they decide to influence the target. A rock thrown a fair distance into the pond splashes only in the middle of the pond and sends out waves that have all but dissipated by the time they reach the shore, but one thrown with too much force or too near to the edge will splash back. Not to trivialise this awesome power with examples of rock tossing, perhaps think of it more like setting dynamite. Regardless of the example used, however, this is also a facet of using the dark ethers that a black mage must consider: how will the spell affect the caster in the end?
Finally, consider that it is wise to remember that simply because black magic relies upon a perspective of negativity, the black magician has no obligation to pursue particular aims or goals simply on the basis of these goals seeming to be destructive. The dark ethers are a tool for the magician to wield, not a master or even a philosophy, and certainly not a religion. The black mage, finally, is cautioned to recall that only that which is already null or void is free from the influence of entropy, so ultimately the black magician must develop at least to some degree a capacity for complete detachment in order to avoid experiencing degradation as a result of contact with the dark power.