Magic is a powerful force in the world of Rezia. While the exact source of
energy powering it is yet unknown at this point, all beings can harness it to
some extent or another.
Scholars typically divide magic into two distinct orders: structured and innate
magic. Structured magic is what most spellcasters make use of, involving specific
incantations and gestures, and yielding predictable results. By comparison,
innate magic has been practiced for far longer, yet is much more dangerous to
use. While innate magic users are freed from the constraints of the
aforementioned incantations and gestures, they must have exceptional mental
discipline to control their magic without those guardrails. If one attempts to
innately cast a spell that they are not intimately familiar with, it may
backfire on the caster.
While it is possible to use magic without the use of any language, almost all
spellcasters opt to use standard verbal and somatic components when casting
spells. These serve to structure the spellcaster's thoughts as they execute any
given spell.
When the Five arrived in Rezia, they taught the mortal races much about magic.
Through their teachings, Celestial has become the standard language used by
most spellcasters. Despite this, however, the use of Celestial is not necessary
for either of those creatures who were already proficient in the use of magic
before the gods' arrival, such as the giants, have largely continued to use
their original languages.
In the Feywild, it is quite common to use Sylvan as the language of spells.
Devils' contracts may be considered a form of spell written in the
Infernal script where signing it constitutes the casting of a spell in some
form. By comparison, demons can use Abyssal for their spells, but many reject
that more ordered approach to magic, instead preferring to rely on their own
innate and primal magic.