Geas

A Geas is an extremely advanced curse which is considered one of the five atrocities of the Kido Corps. As it's capable of doing immense harm to any civilization in which it is practised, not to mention the huge moral and ethical ramifications of casting such a spell. As the spell essentially allows the caster to claim ownership of someone elses very soul.

In line with it's status as one of the five atrocities, it's a forbidden spell to cast, and the Kidou Corps have means of both tracking affected subjects down and dispelling the curse itself. However, despite their willingness to see it broken and the victim freed, there are certain individuals who as of yet are simply too powerful to anger. These individuals wield the spell relatively freely, for with their position they are more or less untouchable.

In these cases, the Kidou Corps are largely delegated to preventing instances of the curse altogether, by warning those who deal with these individuals never to give up their full names. For without the name, a curse of this magnitude simply cannot affect it's target.

Description
Contrary to other curses that deal with controlling someone else, a Geas does nothing to manipulate the victims will or mind, nay, those effects are easily spotted, and typically only last shortly. The power of a Geas is to take complete ownership of someones very soul, to curse them to an eternity of servitude.

The victim retains their mind even while cursed with a Geas. They remain unchanged on the outside, but on the inside their entire being has been compromised. The caster can at any point choose to command their subject, and these commands must be obeyed - the victim feeling an overwhelming compulsion to do as they're told. Should the victim choose to ignore this compulsion and act in defiance of the Geas, it will punish them with great pain and nausea, until they at last surrender to it and do as they're told.

If a target repeatedly defies a Geas, it will eventually destroy their spirit utterly. Because unlike most other curses, who merely attaches themselves to the soul of the victim, a Geas stiches itself into it, so that it becomes a part of the victims soul on a fundamental level. Death occurs when the spell literally shreds the soul apart from the inside out.

Although a curse such as this can affect anyone regardless of their level of power, powerful beings are frequently capable of resisting it's effects for far longer than most without dying. However, these cursed ones still live an existence of perpetual agony and misery for their decision to do so.

However, even with a curse such as this, there can be reprieve for an intelligent victim, for while the curse will enforce the commands of the caster, if those commands are non-specific, the victim is given a modicum of choice. For instance, if a caster told someone to assassinate someone, the Geas would enforce that they did so but the victim is free to take the longest possible route to get there. Provided they were still "on their way".

If the caster is wholly specific however, the curse will enforce every single detail and the victim must obey everything. The most common commands given to a victim is to never do anything that would harm the caster in any way. Whether that be physically, spiritually, financially or politically. The second command is to force the victim never to make any attempts at conveying their status as cursed to anyone, so as to protect their investment. Most of them are therefore forced to live their lives in hope of salvation, or make attempts at breaking the curse on their own.

Requirements
While a Geas is a fearsome thing, it's comparitively easy to protect oneself against. It's also entirely impossible to cast in the midst of battle, due to it's extremely long-winded incantation. Unless the opponent is exceptionally daft, that is.

Birth Name: A standard for almost every curse but the absolute weakest of them, without the full name of their intended victim, along with the exact kanji that comprise it, the Geas can not affect it's intended victim in any way. The name is absolutely crucial.

An Object of Significance: This is neccessary in order for the spell to gain access to the victims soul, and is also commonly required by many other high-level curses. Such an object could be a lock of their hair, an object they adore or have used extensively, or even something they absolutely despise.

Breaking the Curse
There's no form of counterspell to a Geas, quite possibly making it the absolute hardest curse to break. The spell can only be broken by someone of similar skill to the original caster in the art of Henkodo, and it must be done with surgical precision, any less than that and the entwined curse might end up inadverdently destroying it's victim during the treatment. There's however other ways to break it, but these are not widely known.

It's believed that a Fullbringer of exceptional ability, experience and mastery of their craft could extricate the curse from it's victim, thus breaking it. But such Fullbringers are vanishingly rare indeed.

Incantation
"Once there was but two, now only one. The beast of hatred lurks in darkness left by love, an abrupt turn, a shattered mirror, the beast wakes to plague a past. Born of regret, ended by fate, first verse fulfilled.

''The cold breeze of night blows out a thousand candles, a thousand and five hundred more are lit in turn. As with blessings alive, so with tears in the grave. The struggle continues, the barrier rises, second verse fulfilled''.

''O, black star below, I invoke what is and isn't, she who is forsaken, she who was forgotten. The maggot preys on flesh, the vulture on a corpse. Ye who are lost, in my palm I hold the night. Third verse fulfilled''.

''Sixteen arrows, blackened by your heart, sixteen chains, marred by your venom, three simple words, whispered in your name. The serpent that swallows a blade, the misery of fate I decree, upon this tainted memory I invoke a name. A broken heart, the stench of betrayal, a future not to be, thus ends the fourth verse''.

''The hidden moon tilts over and falls, eight islands born of tragedy, let my words be a bridge, and my spirit be a prison. Ye who remains uninvited, by this wicked plea I extend my hand to thee. The widow spins three black webs, the pact is sealed: sacrifice, summoner and mistress, thus ends the final verse''."

Known Practitioners

 * Shigenaga Arma