Forms of Magic and External Casting

Magic comes in four forms: learnéd, innate, gifted, and symbiotic.
Learnéd casters gain their abilities through extensive knowledge, study, and practice - thus, wizards, artificers, and bards are considered learnéd casters. This is the most common casting archetype, as these three particular classes are able to be taught through actual education and not mere luck. The rogue's arcane trickster would also be considered a learnéd caster.
Innate casters are ones granted their magical abilities through circumstances beyond their control, whether their bloodline or environment creates a shift in their fundamental biology towards the arcane - thus, sorcerers and races with born magical capabilities are considered innate casters. The fighter's eldritch knight would also be considered an innate caster.
Gifted casters gain their powers through communication with a higher power or extreme devotion to a set of beliefs - thus, clerics, paladins, and warlocks are considered gifted casters. Since religion is so ubiquitous in Uthilith, these casters are fairly common as well. The blood hunter's order of the profane soul would fall under this category too.
Symbiotic casters connect with the natural world to gain their abilities through honing their senses or becoming one with nature - thus, druids and rangers are considered symbiotic casters.
If one comes across a spell scroll, they can use it without penalty or effort if it lies within the category their class falls - if a wizard comes across a spell bards can cast, they too can cast it. However, if their class simply doesn’t fall within that category, then the caster can make an arcana check (DC 10 + the spell’s level) to attempt a successful casting. Upon a success, the spell is cast as normal. Upon a failure, the spell does not take effect and the spell scroll is not wasted, but the caster who attempted said arcana check will be rendered unable to decipher the spell scroll and thus unable to cast the spell. If one comes across a spell scroll containing a cantrip, no arcana check is required.
The sole exception to this rule is the bard class, thanks to a feature known as Magical Secrets. Thus, bards are able to decipher and cast any spell from any scroll without forcing the arcana check.

Type

Metaphysical, Arcane