The Law of Language: All Magic is harnessed through the use of a "Divine" language, that can be gifted, in whole or in part, by any Divine who knows it, to any Divine, mortal, or Servant; mortals and servants that know the language can then teach it to others by more mundane methods. Monsters, however, exist outside of the power of Gods. Demi-gods can tap into any of these Words their forebearer knows, instinctively. To know the word is to know what it describes. Those who can master concepts are often the strongest mages.
The Law of Essence: The innermost truth of things is described by the Divine Language, and you cannot lie in it consciously.
The Law of Writing: The Language can be written, inscribed as sharp-edged and blunt Runes, or as a delicate Script. The Runes are more powerful, the Script more precise. Power can be stored in the medium the Runes or Script is drawn on, or they can draw power from outside. While there is only one way of writing each Rune and each meaning of the Script, they can be found by experimentation. There are dedicated Runes for each Word, while the Script is made of combinations of symbols, and is much more modifiable as a result, even though it is weaker in raw power.
The Law of Power: Power for magic is drawn from living things. The stronger the soul, the more power can be drawn for magic. Drawing too deep from your own reserves will scar the soul, often harming intelligence, personality, and memory. Going even further can be lethal. Power can be stored in gems or enchanted objects, stolen from other living things, or accessed from any other source of magic decreed by other laws.
The Law of Cycles: Magic waxes and wanes through the seasons, based on the Spheres of the system's creators.
Spring: Ceredi-El, Ceredi-Ur
Earth, Creation
Summer: Quillus-El, Quillus-Ur
Fire, Maturity
Autumn: Shalun-El, Shalun-Ur
Air, Unbinding
Winter: Nikkem-El, Nikkem-Ur
Water, Withering
Note: The way creation, maturity, unbinding, and withering work is as described by Nike:
"a spring [creation] rune would create a tree, a summer [maturity] rune would make it hard, autumn [unbinding] would let it move, winter [withering] would end its life"
The Law of Patrons: Each wizard and mage will be able to choose a Patron God or Goddess. That God may grant them magical boons, such as additional power or knowledge of additional words. Regardless, the magic of their Patron's Spheres (And the Patron can be any god) will always be stronger than other magics for the mage, even in its waning months. Furthermore, even if the patron god is not present in the world, choosing them as patron will still provide the boon, so long as they have been in the world previously.
The Law of the Sky: Important astronomical events (A star rising or setting in a particular place and time, etc.) can also be magically important, should a God decide to make it so, and grant that knowledge to a mortal. However, it must be vetted by the Owner of the System.
The Law of Deities: A God may decide to make something a source of magical power, which practitioners may draw from without fear of exhausting their own reserves. However, these items must have conditions preventing infinite use, and must be vetted by the Owner of the System.
Outside this system, it's also worth noting that stone pillars always contain large stores of magic, though they can be difficult to acces.