Aceso

Aceso (死活の薬用武器 (アセスオ), Asesuo; lit. "Medicinal Weapon of Regeneration and Destruction") is a basic Healing Magic spell that has various uses, both inside and outside of combat. It's used by various individuals, but mainly by mages in the medicine field.

Overview
This spell, despite its simplistic look, is very hard to conjure; it requires one to have precise control over their magical reserves, being able to freely flow it to various parts of the body. In order to conjure such a "tool", the user flows a good deal of magical energy into their hands — refining it to its utmost limit. The end result of such a deed is the creation of a shimmering form of energy surrounding the user's hand. Since the energy is refined, it has enhanced capabilities that far outgo raw magical power when manifested normally; it becomes sharper in quality and more concrete in appearance, so much so that it can be touched & felt. The technique can be used with either one or both hands; the latter being seen in experts of the spell.

Despite its status as a form of Healing Magic, the spell can be used in an offensive manner. It can be used to enhance the user's physical strength by stimulating the muscles within the body using the power emulating from the shimmering mass surrounding the user's hands. However, the true strength of this spell is found in its precision and cutting power. By focusing the caster's hand into that of the knife-hand gesture, they are able to swing the shimmering mass of energy — using its sharp edges to cut through various objects, letting it act like a sword or any given bladed-object. However, there are limits to what it can cut — mainly with objects of high density and the like.

The spell can increase in effectiveness if one flows & refines even more magical energy to their hands. This can either increase the size of the blade — allowing for greater range, or increase the blade's given density — allowing for greater cutting power and precision. However, such a thing hasn't been attempted as-of-date because of two factors that tend to happen. The first is that there's a high-chance that such acts can damage the user's hands because of the over-exposure to the large and/or refined amount of magical energy; this can leave their hands numb for a certain time, putting them at a disadvantage. The second is that such methods take time to perform, allowing the user to be completely vulnerable. If the method were to ever be disrupted, not only would they lose the magical power they've already charged, but they would have to start the process all over — thus expending even more energy. The second reason can be remedied if one has allies to cover them. If that doesn't work, then they could hide in a remote location while they could perform such a tedious task. It's known that few have tried utilizing such tactics, only some coming out successful.

When one's medical knowledge is applied, this spell can be used to cut the target from the inside while not creating any form of external wound; this prevents the risk of infections from arising. It's known that this spell can cut through muscle tissue and tendons. This proves to be of great use in battle, as it temporarily disables an opponent in battle, allowing the caster to land fatal blows or escape. When aiming for precise locations of the body, this spell can easily sever organs (i.e. heart, liver, kidneys, stomach, lungs) and stop certain bodily functions by severing certain joints and nerve endings. This can either cause instant death or irreparable damage.

The reason for this spell's existence is mainly for emergency medical procedures; the technique allows the caster to perform quick medical assistance to those who need it, substituting for the lack of tools one may not have on their person. It's seen in various instances that this spell have saved the lives of many; this made it one of the most used spells in Earthland — being a core requirement for healing-based mages.

Trivia

 * The name of this spell is derived from the Greek god  — recognized as the god of healing of illnesses & injuries.
 * The concepts of this spell are heavily based on the mechanics of the Chakra Scalpel from the anime/manga series, Naruto.