Meditation was a practice he had picked up on ever since he was self-aware. It was something ingrained in him inexplicably at birth, as if some inborn instinct. He did it subconsciously at first, and later when afforded some privacy — he would delve into it purposefully every night.
That was the only coping mechanism that got him through the migraines he suffered in his youth. It soothed his spirit and allowed him to brave through otherwise insufferable days.
Along with this daily rite, he also kept in mind some unusual stances, and repeated that exercise religiously since he was seven. Going through these postures, he developed an athletic body unsuited to his age.
He didn't bear a massive musculature, but rather had a fluid and tempered physique suited to nimble running and such. This way of practice didn't take a great toll on him nor stunted his development. He had inherited a routine perfectly suited to his growth, one that kept him both healthy and energetic.
Getting sick in this age was a crime. Even noble children might see themselves perish, not to mention starved orphans. That is why despite not knowing why or how he possessed that esoteric knowledge, he instinctively put in the effort to perfect and temper his body.
Speaking of instincts and inherited knowledge — Leonardo endured much as a baby. Agonizing migraines kept him crying most of the time, earning a reprieve only when fatigue silenced him and he fell asleep. Perhaps it was due to that reason that his parents left him stranded, guessing he wouldn't be long for the world.
What the others weren't privy to, is that with each skull-splitting headache — some knowledge would seep into his mind from afar. As he absorbed it, his intellect was enriched by foreign wisdom and customs, seemingly from another life entirely.
Most times it was worthless tidbits of history, poems, literature and the likes. Other times, he would perceive blueprints of quirky things he never managed to quite comprehend. It was a chaotic puzzle in his mind, one he painfully strove to solve as he continuously gathered missing pieces from a pond of agony.
He exercised his mind and tried to make sense of it through meditation — the only way he knew to soothe the pain. As time passed, less and less knowledge trickled in, and gradually the migraines became less and less of an occurrence. He suspected most of it was missing, or perhaps it had never existed in the first place.
That said, he was strangely grateful. He was by no means a masochist, but this rather incomplete inheritance paved the way for his survival so far, and also laid out his path to greatness. Through it, he uncovered a True Magic heritage, as well as some martial arts / cultivation manuals. Those roughly translated into: The Road of Virtuous Ascension and Mortal Transcendence.
[Author's Note: Long infodump ahead; TL:DR at the end]
Magic, as he summed up from his memories, was a means of enforcing his will on the world. Yet, to do so he would need to meet specific prerequisites. There were no silly incantations required necessarily. Magic is too liberal for stringent abracadabra or precisely repeated wand gestures.
Magic is all about purposeful will and knowledge. Casting method comes secondary, and is merely an instrument of delivery. The incantations themselves or the gestures carried no inherent power. At the root of it all was the magus himself.
Spells are something instinctual derived from one's understanding of the world, then later expressed through a fulcrum in the form of gestures, incantations, rituals, etc. These depended mostly on one's inherited path or paradigm, and were largely fluid.
For example, a stereotypical Salem witch and Leonardo could both perform a flight spell. Yet, whereas the witch would employ a broom as an instrument, Leonardo might 'step on the air' or use his sword as a platform as is typical of Chinese / Wuxia myths. However, both would be made possible only through their inherent understanding of gravity and momentum.
According to his inherited Path, there were 9 distinguishable steps one had to surpass to transcend Samsara, and 9 Dharma — basic principles of cosmic or individual existence, each corresponding to a specific facet of reality. Namely, these were intuitively as follows:
Vita was the facet that focused on living, organic matter. It unveiled life itself, from microbial organisms to complex genetically engineered chimera. At first, knowledge of this aspect allowed one to sense living creatures and understand their weaknesses. As one delved deeper, one could uncover the means to heal or transform their body, giving it supernatural characteristics.
Materia encapsulates all non-living constructs. From dead wood to complex chemicals, it allowed one to understand and shape physical objects in its initial stages. Later, one could transform their molecular make-up entirely, effectively transmuting rocks into gold.
Elemental encompassed the elemental forces of nature at the base, but it also touched on more obscure physics. Gravity, momentum, radiation and sound being a few of the notable unseen forces. Typically, mages only intuitively grasped those aspects. But even without knowing how to shape a supernova, a summoned tornado of flame was just as deadly.
Tempus governed the workings of chronological forces. It's as hard to master as it is obscure, for controlling time is no joking matter.
Spatium is the element of connection between things. A little more complex than just 'space magic', it focused on relativity and quantum juju. At higher levels, it allowed one to appear in multiple places or dimensions at the same time.
Animus unraveled the mysteries of consciousness and psych energy. At first serving as the means to understand oneself and harness one's emotions, it soon broadened into all aspects of the mind. One could tamper with memories and dreams, cast illusions or modify perceived reality.
Spiritus tapped into souls and dealt with ephemeral beings such as ghosts. It was also essential to master if one wished to unveil additional layers of reality beyond what the mind and the eye perceives.
Fortuna unraveled the abstract principles of fate and luck. From a lucky roll of the dice, to manipulating the fortune of entire nations. It was a potent tool for good in the right hands, or it could be a most horrid weapon. Blessings and curses are part of the same spectrum.
Primal formed the basis of all things from raw primordial energy. It was the source of creation. The spring of all things. Grasping it was difficult but essential to harness the other facets of reality. It acted as fuel for other spells, but as one comprehended it further — one could unravel reality at the core or dismantle enemies into raw energy.
New spells are formed by combining one's understanding of one or more Dharma to a sufficient degree. This comprehension had to be practiced to such a degree that it was almost instinctual.
Put simply with Elemental Dharma and Gravity Control as an example, to read a book about the constants of gravity on Earth is far from enough. A mage had to intimately 'feel' gravity and instinctively comprehend how it interacted with the world at large. Only then would they stand a chance at lowering or increasing its force.
Just as it is with path steps, there are also 9 distinct base stages of comprehension for each facet, though few could grasp things beyond stage 5. One's stage in a specific Dharma dictated the maximum achievable scope of a given spell.
At first stage, a mage could instinctively perceive a specific aspect of the world. Leo had an instinctual spatial awareness due to this innate understanding of Spatium Dharma.
Further on the second stage, one could begin to manipulate small variables in a natural force, as well as perform nifty spells like warping a small apple within line of sight.
Stage three allows one to manipulate an element on a greater scale. You can theoretically pause time, teleport, or summon flames in one's palm.
Stage four greatly increased the scale of what could be done. Where previously a mage could heal scratches, now one could regenerate entire limbs, teleport a chariot or summon a tornado.
Stage five pushed the limits of what is meant to be possible. Metamorphing into dragons, altering life at its source and creating a brand new species. Uplifting islands and dousing volcanoes, the limit of reality became trivial.
Beyond this stage, one had sufficient knowledge to upturn entire continents or shift the poles. However, these spells were very demanding and drew too much attention to be feasible. Even if Karmic Spirits didn't act to turn the mage to dust, other supernaturals surely would detect and stop him.
The degree to which you can comprehend and manipulate reality is limited by your personal path ascension step or self-excellence — a concept dubbed Virtus. One's Dharma stages are also limited by this elusive scale. An increase in Virtus is based on a thorough breakthrough by the Mage in the aspects of morality, virtue, will and soul.
By overcoming one's inner flaws, gaining elevated understandings of the world and enriching their soul, a mage would transcend their current limitations and unlock a greater potential. To increase one's Virtus, one had to pass a perrilous trial of the mind — Quaestio.
The Road of Virtuous Ascension was seldom traveled to the end, however. Across centuries there were only a rumored few who truly reached step 9. The few who passed step 5 were hence known as Archmages.
Knowledge is power, especially for magi. From a small spring flowing into a creek, then a raging river, and ultimately leading into the endless ocean. Such was the pursuit of magic, ultimately seeking to encompass understanding of everything in the Universe. With this knowledge as the basis, they could accomplish anything — so long as they were daring enough to fuck with Karma.