Ice Slave

Ice Sleep (, Aisu Surīpu; lit. "Everlasting Glaciation of the Mind, Body, and Soul") is one of the cruelest uses of the elements, said to have been impossible to conceive through normal means. It's something that's simplistic, yet versatile in nature — giving one complete control over those unfortunate to be its targets. This magic is said to be one of the many inventions of the modern era, thus is considered something of an anomaly to those who are well-versed in the ancient ways of spellcasting.

A Caster Magic, it takes from the principles of Molding Magic and utilized in conjunction with Ice Magic, as the name obviously alludes to; it's one of the many forms of Subspecies Magic — as it also involves the usage of Memory Control, a magic that can act as a form of mind control in the hands of an extremely skilled user. Though not a member of the Black Arts, it's still considered to be heinous in the eyes of most modern mages, thus branded as a Forbidden Magic — utilized only in extreme conditions.

Typical of its effects, it's branded as one of the myriad forms of Subordination Magic — though classified on a lesser scale.

Overview
"What.... What's happening.... My very thoughts are.... Being snatched away!"

- Mavis Vermillion upon donning the frosty collar serving as the medium for this magic.

The elements are considered to be one of the most primitive, yet versatile forms of magic known to Earthland; they're commonly seen used nearly every mage in existence, whether its molded in some form to suit their fancy, used to slay mighty beings, or to simply adjust one's own fighting style. Like all magic, it can be used for good or evil, depending on the nature of its wielder, thus there are a myriad forms of elemental manipulation, even if some of them happen to be unique. However, even though it's versatile it's not all-powerful as everyone believes — possessing its own limitations; even then, such limitations can be overridden in certain cases if a mage proves themselves talented and worthy enough, giving new purposes to said elements that weren't possible prior. Ice Sleep is an example of that, capable of performing something no other element is capable of achieving on its own: Mind Control.

This form of mind control makes use of the ice's properties of effectively "freezing" and "stagnating" anything affected by it. How does one go about it, pray tell? It's rather simple. By understanding everything that the ice encompasses and having the necessary amount of magical control, one can easily invoke unknown aspects of the ice element in unique ways, acting as something else entirely and fooling others into believing that the caster is using another ability altogether. This takes many years to accomplish if one doesn't have the talent, thus magic such as this one is reserved for those with extreme talent for manipulating ice to its highest degree, denoting to its level of difficulty.

In order to invoke this magic, the caster needs to conjure a collar of sorts made from a unique form of ice that's heavily charged with their magical energy — equipping it onto the target(s) in-question; the greater the number of targets or how powerful said target is, the more magical power is needed to form the collar so that one can reign control over said individual. As the collar is applied instantaneously with or without the caster's sudden movements, it's impossible to avoid; It's only when its applied successfully that its effects kick in. As aforementioned, the elements of ice associated with this variation are "freezing" and "stagnation" respectively; in this case, it's aimed at the target's mind and body respectively, slowly turning them into a lifeless puppet at the caster's beck-and-call. This is caused by the heavy discharges of the caster's magical power surging through the collar, flowing through every inch of said target's being and transforming into "ice", metaphorically-speaking. Said "ice" slowly causes their brain and motor functions to cease and slip from the their control, purring it in the hands of the caster. It's originally believed that the greater degree of power the target possesses, the slower the process; this is true in most cases, but in the hands of an advanced ice user, this process is as instantaneous as the collar application — giving no time for the victim to resist.

Once the take over is completed, the caster can command them to do anything they wish — so long as they have the capability to do so, regardless of their wishes. This would include doing the vilest acts and coercing information out of them, two of the magic's most common uses. Due to the freezing temperatures of the frosty collar and the foreign amounts of magical power invading the body, the victim is in constant pain while performing said deeds; this is seen as a twofold form of torture, thus the reason why the magic is branded as forbidden. It's typically used and valued in times of war and conflict, however, as it can forcibly turn and enemy into an ally in a mere instant, giving the caster's side the upper hand. It's also used as a form of discipline, punishing those who are deemed as a "rebellious element", thus is used as a capital punishment in most governmental bodies.

Like all powerful magics, this one has some weaknesses and limitations — most of which deal with skill level, power, and the targets themselves. For one, this magic needs an absurd amount of power and control to cast, especially if the caster aims for one more powerful than them or a larger group of people. Even then, said number is limited as the recorded number of controlled targets is a hundred; any more would cause unnecessary physical, mental, and magical strain on the target. While it works on a wide variety of creatures, typical exception are those affiliated with the ice element itself — having the necessary traits to resist the cold temperatures induced by the collar, and by extension, the altered magical power flowing within, Gods — beings who are naturally above the concept known as "magic", and Dragons — living, breathing, and hulking embodiments of magical power. It's mentioned before that the collar can only command the victim to do things in their power; this mean that one cannot command a blind man to see, a cripple person to walk, or a mage to use a magic they don't know. This also extends to information as well, as the caster can't command one to give them information they either don't know about or have forgotten for one reason or another.

The true weakness of this magic lies with the user; Mavis herself has hinted by defeating its caster, can the magic be dispelled. Thus, should one want to cancel out the magic's effects, then the caster must be defeated at all costs. However, this can overridden if the caster gives control to another person, ice user or no. It's unknown how this can be accomplished, but it's hinted to be done through some form of Pact. Thus, even if the original caster is defeated, the magic still stays until the new controller is defeated. Should this magic be applied for too long, there's a high chance that the victim will lose their individuality permanently, becoming a doll that follows the beck and call of its owner; it's unknown the time period for which this effect kicks in, but its noted to be relatively short, giving the opposition little time to work with.

Trivia

 * The information provided in this article was expanded on from its canon counterpart, thus all credit goes to the original authors on the mother site.
 * Kinda feels like this came out of a kinky hentai, don't it? Also reminds one of a.... certain ice user, if ya get the drift lol.