Formula (魔印強化 (フォーミュラ), Fōmyura lit. Magic Seal Enhancements) is a Caster Magic, one that is considered very "basic" in nature, and involves the usage of Magic seal in order to allow for enhancements to both physical and magical attacks.
Formula requires great control over one's Magic, and Magic energy, allowing them to even manipulate magic seals, without casting a spell using them. By using magic seals, a Mage can "formulate" it to have enhancement effects to their attacks, be it physical or magical. For example, one can create a Formula magic seal that increases the strength of a punch, or a weapon, making it far stronger than prior. It can also increase speed, and durability of physical attacks, thus, it possesses great use, even for martial artists. The attacks must go through the seals in order to recieve their enhancement.
The enhancements are, of course, temporary, and their lifespan depends solely on the user. With great enough skill, they themselves can decide for how long it remains. The longer time it has, the more energy it will use up for the seal. Without involvement, the enhancements last for about 5 to 10 seconds, but can be stretched to minutes, but never to hours.
As for spells, Formula is capable of not only increasing the strength, and speed of a spell, but also increase its size, adding more destructive power to it. However, due to it requiring Formula to be casted first, it means an extra amount of magic energy must be poured in order to cast a spell immediately after.
A unique aspect of this magic is, that it can enhance more than simply "speed, attack and defense", but true masters can go the extra mile, and grant enhancement to even miniscule details, either for themselves or their spells. A prime example being capable of creating a Formula seal that enhances a spell's temperature, increasing it as it passes through. It can even enhance the five senses, one seal each, granting heightened eyesight, hearing, smell and sense.
The seals can even enhance the user mentally, such as increasing their mental capabilities. However, these are much more complex, and require absolute mastery, and are also known for having side effects on a person, making them suffer extremes headaches seconds after the effect wears off. Emotions can also be enhanced, such as anger, happiness, or courage and so on, allowing for more ways to utilize this magic and empowerment.
The seals created via Formula have two sides, the first is the one always facing the user, which, once an attack passes through it, it will recieve the enhancement. However, the opposite side of the seal does the opposite to any attack, be it magical or otherwise, by the same amount it is meant to be enhanced. This means that Formula also possesses minor defensive capabilities.
It should be noted that Formula seals can also grant one enhancement per seal, thus requiring multiple seals to be casted, to add even more strength, and additional, different enhancements. The amount of enhancement added in a Formula seal is typically counted in percentages, with anything above 50% allowing a single punch to create a crater. Some are capable of reaching up to 100%, or even up to 120% by those skillful enough to push above the limit.