Dear Celestia
You asked me for a report on what I know of necromancy. This is a simplified and abridged version of what I understand so far. Telling you everything would likely fill several books if I went into detail. Some of this information I have yet to be able to verify, I have no way to observe the soul, and the methods used by the authors of the books I've read are long lost to time. I hope this at least sates your curiosity for the subject somewhat.
Cycle of The Soul
The soul lives in the bone.
The skeletal system acts as a sort of series of leylines for the soul, with a unicorns horn acting as a medium which can channel, concentrate, and convert parts of the soul to enact the casters will on reality. The horn essentially programs the energy to carry out a certain task, with the brain acting as the programmer. This is known to ponykind as casting a spell. Using magic expends the users very life force in order to alter reality to a limited extent. For the average unicorn, expending their life energy is not a problem they need to worry about, it is restored over time naturally simply by living. Eating, drinking, sleeping, anything that grounds them slowly restores their lost energy.
What we refer to as a soul, is better described as the raw essence of life. It is malleable and very versatile, able to adapt and grow to fit new circumstances very easily. A good example of this is its method of procreating. During gestation of a new foal, the mother slowly transfers new portions of her soul to the fetus. When the foal is finally born, the soul animates it, and uses the physical body to interpret the world around it. The soul grows as its body does, learning more as the brain develops, but remains 'incomplete' until a certain point in the bodies life is reached, and its purpose is found. According to the books I've read, the appearance of a cutie mark ends the developmental stage of the soul. As the soul goes about its life, everything it experiences is imprinted upon it. The soul uses the body as a tool to experience reality. It is a very efficient tool, designed to require almost no help from the soul to be active. Unfortunately, tools can break, and wear out. While the body may be break, as long as it is alive, the soul is still housed there. This is an especially horrific fact in regards to sufferers of brain damage. In these cases the soul still retains its memories and cognitive abilities, it simply lacks the means to express it physically. Normally when the body dies, the soul instinctively leaves, as the body can no longer provide the soul with sustenance and experience. As of right now I believe you may be one of the very few who can know for sure where the soul goes after death, but this is where necromancy comes into the equation.
Revenants
It is possible, through a very obscure spell known as the Soul Cage ritual, to trap the soul in the skeleton of a body. This must be performed within a certain time frame after death, while the soul is still lingering in or near the body. After a brief period of confusion, the soul adapts to its new situation, and becomes what is known as a revenant. It animates only the skeleton, the remaining flesh on its bones becomes literal dead weight, and will rot and decay as it is no longer living. The nearly self sufficient physical body it once had is now gone, and the soul must now expend itself to do everything from basic locomotion to holding itself together. Not only that, but its method of replenishing its lost power is now gone as well. Since the revenant now must use magic to perform even the most basic of actions, without a way to sustain itself it will eventually expend all of its essence. If this occurs, the soul, along with the individual it represents, will simply cease to exist. To compensate for this, the revenant develops the disturbing ability to absorb the life of other living things through physical contact. Essentially the revenant gains the power to steal souls to replenish its own. The revenant is able to absorb the life of plants, insects, and small animals with no real consequence, the energy they contain is seamlessly integrated into the revenants soul, adding to its power. Absorbing the life of other sentient being however, has terrible consequences that will be covered in a later section of this report.
Note: Considering that pegasi and earth ponies do not consciously use magic, I'm not sure if it is even possible for them to be revenants, or if they would just be trapped within the bones until they were destroyed. There is no record of any revenant being made of a non-unicorn.
In addition to the other qualities mentioned, the revenant gains another curious and useful trait. Normally when the soul is bound to a living body, there is a limit as to how much it can grow in power. I have no idea why this is, the soul takes up no physical space as I understand it. Rather than just keep swelling as the body eats, sleeps, and lives, the soul will stop growing once it reaches a certain size that differs from pony to pony. Perhaps there is a limit as to how much power they may contain without somehow harming the flesh of their bodies. Revenants however, have no such limit as far as we know. They have been observed to absorb vast sums of life with no problem, and can store it until they wish to use it. What this means is that even the least gifted of sorcerers upon becoming a revenant has the potential to eventually become nearly godlike in power should he be patient and conserve his energy. This is one of the reasons why revenants can become so dangerous. (I am using size figuratively when describing a soul)
Note: The authors of books regarding souls have noted that it seems earth ponies have a much larger reservoir of soul energy than the other two species of ponies. This is odd, considering they don't actually use magic. Perhaps this is the source of their physical strength?
It is possible to aid the revenant, and allow it to use less energy as it moves about by physically fastening the bones together using leather straps, hinges, or metal plates. This allows the revenant to focus less energy on holding itself together, but requires regular maintenance. These additions also give the revenant a measure of durability, which is useful in combat situations. I have even heard of a specialized suit of armor being made for a revenant that acted both to hold him together, and provide protection. As they no longer have bodies, Revenants do not require any sort of physical sustenance, and sleep is no longer necessary. This also means they have no way of naturally healing themselves. Their bones will decay over time, and require replacement if broken. It is also possible to re-perform the Soul Cage ritual to bind the soul into a different skeleton entirely.
Liches
Liches are why necromancy is considered one of the most despicable of all the dark arts. They are terrifying and nearly unstoppable creatures formed from revenants who absorb another sentient soul. Rather than integrating into the revenant, the two souls meld into one another, vying for control over a single body. The resulting conflict drives both souls completely and irreversibly mad. The Lich completely loses control over itself, absorbing the life of anything it touches. The Lich instinctively seeks out other living beings, inevitably pulling other souls into itself, plummeting further and further into the depths of insanity while gaining more and more power. The only way to kill a Lich is to utterly destroy its physical form, this is further complicated by a Liches tendency to mold other skeletons and corpses onto its body using its malformed magic. The result is usually a massive screaming soul starved monstrosity in the form of a moving pile of rotting flesh and bone. Storms of chaotic dark magic usually surround such things as they lose control of their vast amounts of power. There is no known way to reverse Lichdom, it is imperative that the Lich be destroyed before it absorbs too many souls. A single Lich is capable of killing hundreds, and each time one has appeared it has had to be incinerated with the concentrated power of the sun. They are without a doubt one of the most dangerous creatures in existence.
Known Liches throughout history:
Sanguinious Dracul III
Heinhoof Kemmler
Silver Tongue
Darkblade Evildeath
Mortis Rotgut
Karen Bones
That covers just about everything, you should now have a layman's knowledge of necromancy if you didn't already. Let me know if you have any questions, and I can go into detail.
-Pale Bones
Authors note: Thank you to my readers so far! Any and all feedback is appreciated.
While it's somewhat of a break in the narrative, it is extremely helpful in understanding the additional lore in your story. I imagine getting all this across in a conversation would have been a fairly boring chapter, while getting to read your interpretation of necromancy here was actually entertaining.
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I considered the possibility of slowly dropping all this informaton over the course of the story, but it would have been really difficult for me to do well, and the reader would have problems putting it all together. Plus, by setting the ground rules now, I cant be accused of just pulling some ability nobody knew revenants had out of thin air later.
Some interesting ideas on how necromancy would work...
How about the classic "Speak with dead" magic? I can see it working by either calling up the soul of the departed, or examining the 'imprint' the soul left on the bones.
While I don't see where you intend to take this plot-wise, you might consider Pale Bones doing an essay on common misconceptions about necromancy.
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I have a pretty good idea of where I'm going to take this story. You'll probably have a better idea of what his job entails by the end of the next chapter. I'm not sure whether or not I'm going to make the essay thing a common theme. I actually really REALLY like to explain magical things in a way that almost makes sense. I'm going to try to integrate these explanations into the story from now on, but we'll see how things go.
774904 Ah, I like the whole, "ground rules," idea. That purpose never occurred to me; I just saw the title and got excited at the prospect of storing another fictional interpretation of a kind of magic in the back of my mind. Come to think of it, I may get excited by some strange things.
774980
I'm all in favor of authors having good, solid explanations for things ahead of time, and sticking to them as the story progresses. (That doesn't mean you have to SHOW all of those explanations, but...) It's a very good way to avoid plot holes and inconsistencies later on, which can kill a story's immersion.
Anyway, added to faves so I can see when you update this.
Heinhoof Kemmler? Might you be referring to Heinrich Kemmler, necromancer extraordinaire responsible for starting World War One and Two in a certain book series about a wizard?
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Sounds legit to me. Still cracking up about "Darkblade Evilhoof," poor guy must have been teased mercilessly in school.
People notice Kemmler, but not Karen Bones... possibly related to the latest practitioner?
But what about the Soul-Jar/Phylactery form of Lichdom? Where you synthesize and remotely possess your corpse, having bound your soul to an object?