Magic

Magic refers to the powers that those with Cores can use. There are a wide variety of magical abilities ranging from simple household spells to complicated shape-changing magic. Magic can also be used to make potions or magic items which themselves hold magical power and have magical abilities.
Most people can only do a few simple spells and use basic magic items, with most relying on magic objects rather than casting their own spells. In order to do more advanced magic, one must have a stronger more developed core which involves having exposure and training with magic as a young child and having a natural talent.
Advanced magic requires a strong, well-developed core and allows for more complex magic spells like healing, shapeshifting, weather manipulation, and wards. These spells are more powerful and with outcomes that far outpass a simple cooking spell. Those that have developed these abilities are called Magic Users.

Light & Dark Magic

Good and bad, white and black, healing and hurting. These are the various terms used to describe the two generally decided-upon categories of magic called Light and Dark magic.
People tend to assign certain spells to each category, but realistically, magic is grayer and can be seen as light or dark depending on the intent of the caster. If one has more bad intent while casting a spell it would be considered dark magic. If one has more good intent while casting a spell it would be considered light magic.
This does lead to specific spells that require a certain type of intent to be assigned to a certain category. For example, if one casts a spell to harm or kill someone, outside of protecting one's self, would be categorized as dark magic because of the intent to harm. And if one casts a healing spell or protection spell would be categorized as more of a light magic spell -or if the caster has more of a selfish motive behind the action a gray magic spell. Harming someone through the use of dark magic is illegal in Autara and is strongly punished.
Dark magic spells and magic cast with dark intent cause harm to the casters by the formation of Dark Marks. Light and grey magic have little to no effect on the user.