Introduction
In the beginning of time, a great chaos rang out into the empty nothing. A billion newborn sparks burst from the void, shining brilliantly into the inky abyss. Amidst the void, the sparks began to coalesce and churn themselves into unfathomable beings of light. The gods formed from stardust, soaring through the new universe as they created the realm with nothing but their own bodies. There they would fly, weaving and playing in the ever expanding world for billions of years.
There, they would create magic.
Magic is known as the essence of the gods. Everything in the realm, be it a blade of grass or a neutron star, is formed from and uses up some level of magic. Up to 99% of all magic in the universe is known as mana, magic derived from the environment and the inanimate. Mana maintains the fundamental rules and processes of the world, acting as both the blueprint and the materials for creation.
Magic has no limits to its use, and can be manipulated in an unfathomable number of ways. But it is contained through its supply. The gods only had so much of their being to give.
Sentient Life
After billions of years of creation, the majority of the gods' essence had been used up. But, they still had more to make. Thus, all nine came together to create their last planet, a small, unstable, and wonderful thing, the Selvan. From there, they would pull magic from their own intelligence to create beings much like themselves. They created life, beings that could grow, create, and manipulate the magic around them.
A spell is any magical process (i.e., any instance in which magic is used to create, destroy, or change something) facilitated by a sentient being. Spellcasting requires a being to channel the deific magic within them, allowing them to use the same powers that the gods used in order to create the world.
Most if not all beings are born with an instinctive grasp on spellcasting, allowing them to manipulate magic but restricting their ability to learn and cast new spells. All living beings are supported by the magic of their corpora, mana which has coalesced to support the process of life within a creature (e.g., the corpora of a wolf is responsible for the maintenance of their respiratory system, digestion, nervous system, etc.). Whether or not organisms such as plants or fungi possess corporas is heavily debated.
The Intalli
Yet, some beings possess an even stronger grasp on magic. Some could not only wield magic, they could learn and create new spells altogether. These beings are known as the intalli, the only sapient beings of the Selvan. The intalli were formed not just from the intelligence of the gods, but their consciousness.
The first intalli species ever to be created were the mauhn, the children of Oiana. Filled with curiosity and competition, the rest of the pantheon followed suit, creating their own children in the image of the mauhn and yet twisting them into their own unique forms. From there, the intalli filled the world with newfound beauty, chaos, and bloodshed.
Shapeshifting
All extant intalli species possess the gift of shapeshifting, able to change between a primal, animalistic true form, and a bipedal mauhnic form. While the true forms of the intalli possess a wide range of shapes and sizes, the mauhnic form unites the intalli under their resemblance to their extinct predecessors.
While animalistic in appearance, intalli are just as intelligent in true form as they are in mauhnic. The intalli true form is, as its name suggests, the basal form of the intalli. Intalli are born in true form and are unable to shapeshift in the first few months of life. When an intalli experiences immense distress or pain, they may instinctively shift back from mauhnic to true form. True form intalli range heavily in size, with the sulkan rivaling whales and the ortio similar to a large dog.
The mauhnic forms of the intalli are far more uniform, with all species shifting into bipedal, upright bodies. They have a significantly narrower size range, with all species ranging in height from four to fifteen feet tall with an average of six foot seven (Barring the sulkan). The size of an intalli in true form will scale to an equivalent height in mauhnic form.
While the act of shapeshifting itself is a skill, staying in one form or another does not require maintenance. Intalli which shapeshift often and early on in life are able to shift faster and with more ease than others. Shapeshifting requires a certain amount of focus to achieve and can easily be disrupted (In which case the intalli will snap back to their original form). Some especially skilled intalli are able to flip back and forth between forms, even during a fight.
Pulsars
Deep within every intalli, a spark of primordial magic lay, known as a pulsar. A pulsar responsible for the sapience and spellcasting abilities within the intalli. It also acts as the soul, possessing the intalli's personality, memory, and everything that makes them a person. The pulsar is connected to the body by the brain, allowing the intalli to learn new spells, a feat otherwise impossible with just the corpora. The intalli are the only creatures* capable of learning and casting spells beyond their instinctive skillset.
The size and strength of a pulsar is unique to both the individual and the species. Some species may possess several times more magic than others, but individuals within that species may have weaker pulsars in comparison. The size/strength of one's pulsar determines the amount of magic that is available for spellcasting at any given time. Every unnatural (non-instinctive) spell that an intalli uses requires a certain amount of magic to be drained from their pulsar. The stronger or more complicated a spell, the more magic it requires. When the magic within a pulsar is drained, an intalli will be unable to cast any more spells... safely. The amount of time needed for a pulsar to regain its magic stores varies from individual to individual but may range from only a few hours to an entire day. Rest, food, and relaxation will encourage the restoration of magic. A sickly or injured intalli may take far longer to gain back their magic.
Along with their pulsar, intalli may also be able to draw from the mana around them- given that their pulsar is not empty. Before maturity, an intalli may even be able to expand the depth of their pulsar through regular mana drainage. Mana drainage is far easier for juvenile intalli and the majority of trainee spellcasters are taught to take advantage of this time for a far stronger pulsar in adulthood. For mature intalli, the act of draining mana is an immensely difficult process, requiring intense focus and strain for a fraction of the magic they could gain from simply waiting.
When an intalli's pulsar is empty, any attempts to cast a spell will naturally draw magic from their corpora instead. This is an extremely dangerous act due to the highly specialized nature of corpora magic. An intalli who attempts to cast an unnatural spell from their corpora may be tearing apart the magic which maintains vital internal processes such as the beating of their heart. This can very easily lead to severe, permanent internal damage or death.
Unfortunately, mana cannot be drawn in with an empty pulsar. Mana requires an anchor of pre-existing magic, so a fully drained pulsar will be completely unable to pull any in. But, a pulsar is always creating new magic. Thus, pulsars are rarely utterly empty, even when an intalli believes it is. If there is still the smallest amount of magic left in the pulsar, mana may be violently drawn to the empty space. This can create a violent vacuum effect, causing a catastrophic amount of magic to slam back into the intalli. This can irreparably damage or even destroy both the body and the pulsar.