Increasing your cultivation base is like putting keys into a door, no matter how much one unlocks it could always be locked back up, the 'keys' could be damaged, or the keyholes might not be well done. Cultivating spells, however, is like constructing a building, while
It is possible for it to potentially be lost, it would require actively trying for their magic to come out as weaker than its current level of development.
As things stood now, Sora was a pinnacle early-stage basic mage with a thoroughly built foundation at each level, however, now he needed to get the Basic spells of his awakened elements, Lightning and Fire, past the lesser stage to the basic stage, maximize their efficiency and increase his spell casting speed. He dedicated the last day of his first week to reviewing the casting paths of both spells within his elemental cores.
The fire element basic spell, Fireball had a relatively simple Casting pattern, it was shaped in a spherical ball and simply required the mage to link that ball to the shell of the Elemental core, once they did they could ignite however much mana was put into the casting of the spell and would have full control over how the spell was launched. This however was the wrong way to go about it, Sora discovered in his years of research that all of that was an unnecessary add-on that mages discovered to help them control the raw amount of mana required to cast spells, it helped mages keep control of their spell but wouldn't bring out even half of the spells already sealed power.
Instead, Sora discovered one could abandon the mana paths altogether and simply fill the 'Basic section' of their elemental core with mana and ignite it, which would create the effect of releasing fire in a spiral form. To further refine it one could, after igniting it split their consciousness to shape the spell inside their soul space while simultaneously controlling the form of the spell in the real world, This way you could fully control the spell without the need for useless patterns that limit its output. The reason this was possible was the fact that elemental cores themselves had specific abilities they granted at each level, these 'spells' magicians use are simply ways to control these abilities even at the cost of most of the spells' potential power.
In any case, the process of actually casting a fireball was simply partitioning his mind and flooding his elemental core with mana, he would then 'ignite' said mana and have his second 'active' consciousness shape the ignited mana into the fireball.
Sora went through this process and found himself underwhelmed by the results, his fireball was the size of a basketball which was better than the normally cast one that was the size of a football, It had the golden flame of destruction applied unlike normal fireballs, and the heat coming from it was 10 times as intense as the normal fireball but he had a theory that he needed to test. Sora partitioned his mind once more and cast a fireball his way again except he made a conscious effort to filter the golden flames of destruction out of the spell.
The 'normal' spell he cast was still larger than most Fireball spells, but it was barely 3 times as intense and had barely twice the intensity of flames. Sora wasn't fully sure what a full-powered fireball was meant to look like but this was underwhelming, to say the least.
Before he attempted to improve from a lesser Fireball spell to a basic fireball spell
The reason this was possible was the fact that elemental cores themselves had specific abilities they granted at each level, these 'spells' mages discovered were overly controlled and restricted versions of the abilities the elemental core levels provided. The fire elements' basic ability allowed the user to create, condense, launch, and combust fire; the mana path that was commonly used mitigated the creation and combustion in exchange for better control of the release and combustion.
On one hand, Sora's method was weaker short term due to lack of control, but when practiced to Mastery it becomes a truly dreadful spell to master. Sora's goal for fireball was to be able to instantly cast 5 simultaneously, all having the highest possible quality and intensity of his sun flames, he wants them to be the size of a table tennis ball, and wants to be able to launch them at speeds that allow for them to travel a kilometer instantly, and lastly, he wanted them all to be filtered to the point that he achieves perfect combustion without fail everything. All this while also trying to cast the spell in less than a tenth of a second he sees no need to be able to cast faster than that.
The lightning element was slightly similar to fire as well as significantly more destructive in certain scenarios, a basic lightning elemental core allows a mage to create, gather, intensify, and launch sparks of lightning. The only part of that sequence that isn't self-explanatory is the process of launching.
There are three ways a mage can 'launch' the spark spell, One is the basic means of imploding it on the body part you cast it through and Attacking that body part, the second way is shooting out like a lightning bolt, and the third way, which is not as commonly used, is to channel the spark through some sort of weapons and apply one of the first two ways. Spark generates anywhere from 45,000 to 90,000 volts on its own when cast within the limits, with Sora's dark purple Lightning increasing to anywhere from 75,000 to 150,000 volts across the board, and this was the diluted version.
This very power that spark holds when cast properly is why one is forbidden from casting it on mages as it is the very reinforced bodies of mages after awakening that give them a chance of survival. With Sora's method though, that chance potentially withers to nothing. If you cast it Sora's way the normal spark generates anywhere from 1 to 250,000 volts of electricity while his dark purple Lightning generates anywhere from 5 to 5,000,000 volts of electricity. This method gives the mage full control of how much they singe their opponent once mastered fully.
Sora planned to be able to channel any number of volts instantly and with perfect control of how it affects the targets; he then plans to be able to wield his spark like a glove or a boot, shoot spark into at least 10 bolts, and perfectly channel lightning so it made the tool or weapon that was made of lightning gaining the paralysis effect, the high voltage and the burn all in one sweet singe.