Soul

Soul is a lore concept within the expanded universe of Misery of Magic. It is an idea which appears to mostly apply to the Domain of Magic.

Effects of Soul
Most characters in the game have a soul. The soul is required in order to become awakened and access the Psycho Power.

The soul may or may not contain a latent colour of magic. Once awakened, this colour becomes usable. Having no colour is called being a "Neutral" -- thus, awakening does not upgrade magic in the same way. An "Ultra" possesses an affinity for all three colours at the same time, although this is rare. It does not appear to be possible to have an affinity for exactly two out of three colours.

Light and Darkness
The soul has a balance of light and darkness. While an approximately equal split is ideal, the effects do not become important until one side becomes extremely dominant. If the soul becomes either fully light or fully darkness, then that causes terrible irreversible changes in that person. Once this happens, it is not possible to return to a normal state.

If one's soul becomes full darkness, then that person becomes incredibly nihilistic and stops caring about his own wellbeing. It also makes one's magic weaker. Pure darkness is contagious, in that being near a person of pure darkness slowly drags one's soul towards darkness as well. The effect is subtle, however, so a person with a healthy balance will be able to resist its effects for a substantial period of time without falling into pure darkness.

Pure light is more insidious: it gives people a tremendous sense of purpose and an inexorable desire to change the world, regardless of what the consequences are. It makes one's magic stronger instead. Only the Hero of Light is known to be pure light, and no characters are known to be pure darkness.

Soullessness
A small number of characters are known to not have a soul -- these include characters created within the Domain using the End Tools.

Those who lack a soul can never become awakened or use the Psycho Power. However, they can have access to colours of magic by default -- Max Balewood uses blue magic, for instance.

Not having a soul makes somebody immune to the effects of light and darkness mentioned in the previous section.

Manipulation
Tairi X possesses the Dark Armour, an artifact capable of adding darkness to one's soul. However, it does not work if used on somebody who is already pure light.

The End Tools may be able to control souls as well, although it is not clear how this works, if it is indeed possible.