There are a variety of souls, but once a soul has been rejected, and deemed too wretched or impure, the soul becomes known as a dreaded soul. A soul, that neither world's, wants anything to do with. But this was merely a naming given out of haste a lack of classification in the face of necessity, in truth the correct classification for the abhorrent soul of the Knight, the thing it carries as itself that can barely be identified as a soul, or even as a mock soul of the void, a Vile Soul would be a more valid observation.
Then the book continued to explain the deep peculiarities with how the formation of the abominable soul of the Knight. The details surrounding what happened, not why. There were so many inconsistencies in the formation of the soul thus, it even destroyed the Knights human memories.
Then after the extensive analogy of the Knights soul it moved on to the aspects that govern how souls work. First is skills, which are properties about the world around them. That is why skills depend on the environment and the soul. Skills are not rare, but there are skills that resonate more with specific souls, these are known as special skills.
Most beings possess one of these but the stronger a soul is, the more it can withstand, thus possessing multiple special skills. While any being can learn a special skill of another, its soul will never be able to draw out its full potential. These skills are learned when an event resonates with the soul, making a deeper imprint of the property, more than usual skills.
These skills are carried unto death, so in some cases a baby will be born with a special skill, which is usually a sign of rebirth. The skills are also tied to the soul such that when a soul becomes stronger the skill grows, and this happens at around ten levels for normal souls, but the stronger more resilient souls with more potent special skill have to amass more power to allow the skill to grow.
Next is what is known as powers. These are inherent to the shape of the soul itself, and since each soul is unique in shape and composition, even with the lofty classifications, powers are not shared. Some strange powers can be transferred, but these only one soul can have fully, some powers are not as potent as more beings are using it.
Powers are even more unique, they appear when the soul takes its permanent form, which is hard to achieve. A permanent form cannot be reformed even in the realm of suffering/reform. Once a soul has become permanent it either subjugates a property or creates a new one.
Powers are an expression of a property rather than an imprint on the soul of a property, which resembles the original property as skills are. Usually, a soul can only handle one power before it collapses, and becomes oblivions new joy, joining the void once more. Soul training is even capable of allowing a soul to handle two at most. Some powers are deadlier than most. These need the soul to evolve to be able to hold its shape and become permanent.
When this evolution of the soul occurs so does the vessel, and this is how other types of souls other than pure souls are formed, or from birth nowadays. These evolutions are deeper than just physical or on the soul, the property itself makes itself familiar to your soul. Children born with a permanent soul due to their parent usually have it harder, because the power they can use is limited to the one. That's what makes pure souls so versatile, the ability to subjugate any property, and gain power.
Evolution will be dealt with latter. The souls that are terraformed into the shape of a property at birth are unable to earn any power other than the one it has. But to even use the power, without experiencing oblivion, the soul has to reach the minimum level required by the power, to the activate it so that it can start to be used. The more deadly a power the higher the power stat must be to use it. The example with the Knight is that the visage of terror power needed the Knight to be level 100 and above, so it struck it lucky by choosing the knowledge will, and if it had taken the fifty-level punishment then it would have lost the use of visage of terror.
A dreaded soul is terraformed to have the shapes of two to even three powers. Due to the conditions surrounding the formation of the Knights soul, the first and only ever to be vile soul, has been vilely shaped for seven powers, which would have been impossible if not for the fact that the void has been infused into this soul. This means the Knight will have to work even harder to activate the rest.
There are also type of souls that have mastered changing their shape and can use strange powers. As with everything, there are varying types of cases, strange soul form and composition to allow some pure souls to even become strong enough to use three powers in its lifetime.
Another thing when concerning power is that the stat can only reach up until a certain level until the soul can bare the power. An example is the unnamed baby, it would have died if it reached level 30 and above, that is why turning into a monster would have allowed it to bare more power.
The amount of maximum power a soul can ever be able to reach depends on composition and not shape. The composition has to do with how the soul mingles with the world around it, losing pieces of itself and using the world to replace them. These are what's known as impurities, better labelled as changes. This is why when monsters stay close to a void source, they can absorb some of it and slowly become more powerful and raise their power level.
Some areas of absorption like the void gateway, are like traps, they make an area around them allowing anything within its field of effect to not leave, while still allowing growth of power. The second way to grow if not absorbing from something like gemstones and feeding on impure souls, is to train. By slowly tempering your soul through arduous but meditated training, a soul can gain power, there are other ways possible, these are harder or easier depending on the soul, but mostly they are not universal to all souls like the first two methods.
Then it continued to add details about the niche ways one could become more powerful, going over intricate detail. There was also a listing of sources that allow growth, why? And the side effects they have on particular souls, like how pure souls that feed on monsters slowly become monsters themselves. There was also a comprehensive analysis on the physiology of souls, how they work and mature, what substances could affect them, their ins and outs. Everything and everything there is to be known about souls.
There is something vital that needs to be added to soul growth. The wills. While less substantial for most souls they are the guiding principles. The forces of the world, believe it or not, as decided by the Beginning and End are always working for a creature. Thus, when something has a will, this allows it to be able to shape its soul or otherwise garner it strength.
Wills allow the beings to choose how the world will assist them. An example is the Knight it chose the will of wisdom, allowing it to grow more powerful with the gain in knowledge. And when the Knight accomplishes a task it receives books, containing information about the worlds.
Most pure souls live in the will of reality; this will grant them miracles at their behest according to how much they want it. There is also the will of madness inherited when becoming a monster, this will allow monsters to evolve their forms when sufficiently powerful. While there are multiple wills in the world, they are only there to help smooth things along, while they can be debilitating at times.
Like the will of wisdom refusing the growth of power without knowledge, or the will of reality which refuses pure souls the things they have convinced themselves they want when the future has dictated that they do not want it. Wills serve a purpose to assist not dictate things, like how the will of reality will not stop a pure soul from destroying itself, if it does not seek its aid. Wills are a separate matter from souls, this is merely an observation as to what roles they serve in souls.
Then came the next topic, evolution. It's not quite evolution, this is what observers have resorted to calling it, the more accurate term would be manifestation. Once a soul changes shape, to accommodate the learning and use of a specific power, the change for spirits is visible as in their forms, but for beings with temples, known as bodies, their change becomes manifested into the form of their temple.
Mostly all pure souls take the form of humans, when a soul becomes mad and takes on the shape of that madness, they become monsters, and this is one of the simplest manifestations, it twists and mangles the soul beyond recognition to give it unbridled power. There are multiple species that roam the living world, and that is because ages ago sets of pure souls all manifested into their forms and then became the ancestors. The descendants of these terraformed souls are born already manifested the form.
An example would come from the forest folk. There was a group of humans who decided they wanted to be more in sync with nature, of course their conception of what nature it was flawed, lacking the comprehension of the forces of the universe that be to be able to dictate what actually defines nature. In their misconceptions they chose the forest and all that dwells within it to be nature. This included plants, soil, water, and more.
The power they were hoping to gain was the power contained within the natural disasters of which man was incapable of facing then. The added power they gained was the ability to use the energy within these things to wield inconceivable amounts of power.
The first generation, the ancestors had gained multitudes of power all relating to their understanding of nature. This power is different for all but mostly concentrated on these concepts. Immediately when their forms changed, they were able to use this power. Later on, their children, the second generation was born. They were born with a power, and this power needed set conditions to be met to allow its use. The simplest conditions would be to reach a certain level of power but for some the condition was just to have a profound connection to nature, that is why the rare talents were able to use their power from a young age.
The cost of having changed the form of their souls was that unlike pure souls, they lost the ability to propagate as easily, that is why the human settlements are the most dominant. Some of this is due to the soul cycle. Terraformed souls take longer to make and even fewer of them rebirth. Also, an unintended benefit is that their soul can live longer due to their temples 'bodies' being sturdier.
They even came up with new ways to live, to keep them from destroying the forests, their source of power. The next thing is that after a couple of generations, the ancestors and early descendants, would get permission from the realms and come as spirits, they would aid their descendants with their strength should they ask. Thus, the forest folk were born, a species that has powers and skill around 'nature' and can converse with spirits naturally.