Magic

Magic is a fundamental type of energy in the universe just as heat or light. No matter how the universe originated, whether from a big bang or not, magic came with it, just as heat, gravity, and matter did. However, unlike every other energy, magic is basically the counter to entropy. Magic in the beginning was in vastly small amounts, and thus not usable for a very long time. However, in recent years, magic revealed itself through its natural exponential growth throughout the millennium.

Magic has properties just as sound and light do. Magic is naturally attracted to insulators that work on other types of energy, such as charcoal or wool. Yet, magic abhors metals of almost any kind. Metal cannot be imbued with magic by any normal measure, and is a natural insulator to magic. Thusly, a knight clad in steel will probably kill any equally-skilled mage.

To use magic, one must simply imagine their spell and its effect. If you want to burn a town down, imagine the wood slowly succumbing to the flames, the people writhing in agony. Magic also requires magical energy, of course, which is generally garnered from the air around a being, as well as physical energy from the being that casts a spell. If a magic spell requires excessive amounts of magical energy, one can use things like coal imbued with magic as batteries.

Magic also has a general 'refining' affect on those who use it. For example, an amateur mage might be fat in order to have the stamina to cast an excess of spells, but a professional mage cannot due this because the magical energy coursing through them will naturally refine their bodies and make them 'perfectly proportioned and beautiful' to most.

There are also sentients who use magic naturally, such as giants or dragons. Dragons and giants both contain huge wells of magic inside of them that they feed off of, able to sustain themselves solely upon magic because of magic's exponential growth. They are also able to use this magic naturally, and the magic inside them refines their bodies to the point of making their bodies incredibly hard, allowing such massive weights to be sustainable.