Nen

Nen (念, Mind Force) is a technique that allows a living being to use and manipulate their own life energy (known as aura). The word "Nen" can also be used in conversation to refer to aura.

Creation and Use


Aura is the life energy produced by all living bodies vital for survival. Aura from all parts of the body has a tendency to flow together, producing one mass of energy. This happens without the individual's awareness, typically resulting in a slow leak of aura continually escaping the body. If one were to lose their entire aura, it would be equivalent to using up all the energy keeping them alive, which would be fatal. The pores or points on the body from which aura flows out from are called "Aura Nodes (精孔, しょうこう) shōkō)." Controlling those nodes is the first step to being a user of Nen.

Learning to use Nen is the final step in becoming a professional Hunter because most contracted jobs require the use of it as the minimum requirement. The technique has the ability to enhance the strength of physical attacks or objects depending on the quantity of aura employed and an individual's aura type, as well as allows for para-psychological abilities to exist in reality. Because one can craft just about any sort of psychic power through only using their mind, Nen is also a dangerous power unknown to the public at large.

Learning Nen and Initiation
A student learning Nen trains to manually open and close their aura nodes so that they can control the flow of their aura. One typically learns this process slowly and gradually through meditation. The second method (colloquially called Initiation or Baptism) is by having one receiving an influx of aura from an experienced user that forces these nodes to open; despite how quickly it works, the method is typically frowned upon due to its danger to the student if the user is inexperienced or has malicious intent. Initiation via physically attacking another with the use of an enhanced aura typically causes permanent disability or death.



There is, however, a way to initiate that is less harmful to the student's body — depending on gently jolting open one's nodes forces the new user to learn to control their aura flow, else risk suffering severe exhaustion or death. Once one has opened their aura nodes, he will be able to see his own aura as a shroud surrounding the body due to his nodes in his eyes being opened. Aura appears to look similar to steam from a kettle.

It is possible to feel the presence of aura even without being aware of its existence. It has been described as feeling like a warm, viscous fluid at rest. It has been said that powerful, refined auras produce a sensation that feels akin to needles pricking into the skin. Since every living being emits aura subconsciously, learning to sense aura is a useful skill for those tracking living things or hunting non-living things infused with aura. An experienced user of Nen can judge the location and relative strength of his opponents through reading the output of their aura.

Upon his introduction, Wing taught Killua and Gon a fake sense of Nen that focuses mostly on meditation and on one's self. This method does not require any aura and has no visible effect; however, after Gon was injured by Gido and forbidden to use Nen for two months to recover by Wing, both Gon and Killua practiced this method, and in fact made it more natural for them to use regular Nen. Given that Nen is linked to emotions and mental state, this method can be particularly useful to train Nen without aura, although normal use of technique is usually preferred.

Geniuses


Nen is like any other skill, in that there are those who will learn it faster than others. Some are able to discover and learn to manipulate their aura on their own without having formally learned it. These individuals are typically known as "geniuses," "psychics," or "superhumans" to the public. This can be anything from inadvertently being able to use the basic techniques of Nen or unconsciously developing a unique Nen ability that can be used without really understanding how or why one is able to do so. Typically, geniuses of Nen are exceptional artisans in their own fields and their abilities are related as such.

Notable Geniuses within the series include:
 * Neon Nostrade, the fortuneteller.
 * Benny Delon, the mass-murderer.
 * Zepile, the sculptor.
 * Komugi, the Gungi world champion.
 * Alluka Zoldyck, the Miko.

Nen and Emotion


Although the production of aura is unconscious and constant by all living beings, it is not only life energy. Aura carries with it the desires and emotions of the one who deploys it, which is what allows for Nen to have incredible versatility to those who develop their skill at using it, and also heavily influenced by mental condition and emotional state. A basic application of this phenomenon is that one can channel their aggression or malice into their aura and deploy it towards another person (i.e. blood-lust). The antagonized will then be able to feel that blood-lust as if it were physically palpable; if unable to keep it from their own body by deploying their own Nen, he/she may be physically harmed by it.

Vows & Limitations


Being a product of the mind, Nen responds to the goals, strengths, and desires of individual users. As a result, a student of Nen can increase the overall power of an individual skill by stating a self-imposed restriction that forces even more conditions on it. For example, if one consciously decides something along the lines of "I will only use this skill on Thursdays" or "I will only use this skill against short people" and manages to abide by that rule, that particular skill will become stronger. These conditions are called "Vows (制約, Seiyaku)" or "Contracts". The stricter the Vow, the more one's own ability is strengthened. It is also implied that Vows that carry great meaning or are tied to emotional states also bring about a greater benefit. However, Vows are also considered liabilities, since breaking a Vow carries the risk of completely obliterating one's own Nen abilities.

Vows that contain some sort of punishment (i.e. "I will die if I break this rule") will strengthen the ability even further. These are called "Limitations (誓約, Seiyaku)"—covenants to oneself. An example of this is the character Kurapika, who swore on his own life not to use an ability on anyone but the Phantom Troupe. Even though a Vow adds further Limitations to using one's Nen ability, a Vow is not the primary condition for an ability's activation and acts only to enhance its power.

Exorcism


Nen can be used to place a curse upon others. They are considered dangerous due to their long-lasting effects. Curses may disappear if certain conditions are met by the cursed, but they can also be removed through the use of Nen. Those who possess the ability to do so are called Exorcists, but are rare among Nen users. There are fewer than 10 people in the entire world whom are powerful enough to exorcise Nen curses left by the dead.

Notable Exorcists Include:
 * Abengane, the shaman.
 * Hina

The Unknown
Though Nen is influenced by one's mental condition and emotional state, it is difficult to judge exactly how these factors affect Nen. In certain instances, these factors may even lead to one exceeding the 100% limit cap. However, one using his powers beyond their capacity will ultimately cause strain. Potentially, this could become either a weakness or fatal to the user. Gon is the example of exceeding the 100% limit cap after he enters on rage state that Neferpitou cannot bring Kite back as his wish which makes him totally off guarded from any type of attacks.

Nen also does not necessarily disappear following death. In fact, sometimes death can reinforce an ability's strength. If someone dies holding a deep grudge, his Nen will remain and seek out the object of his hatred.

Four Major Principles


In order to fully grasp Nen, one must first learn the Four Major Principles of the Shingen-Ryu school of Kung-fu. Everything else, including a practitioner of Nen's individual skills, is based on the basic manipulations of one's aura flow. The Four Major Principles, in order of study, are:


 * Ten (点, Point): Focus the mind, reflect upon the self, and determine the goal.
 * Zetsu (舌, Tongue): Put it into words.
 * Ren (錬, Temper): Intensify your will.
 * Hatsu (発, Release): Put it to action.

These basic techniques become second-nature to those experienced in Nen. For example, a beginner must learn to use Ten and concentrate to maintain it; whereas someone with experience will practically always be in a state of Ten, even during sleep.

Nen and Individuality


There are six types of aura; every individual is born having one of these six different aura types. Upon learning one's own aura type, a student of Nen can set about learning to apply the technique in a unique way that suits their personality, which can develop into a unique skill.

The most popular way of determining one's aura type is through water divination. Divination requires one to float a leaf atop a glass of water. A student of Nen will place their hands around the glass and perform Ren. The resulting effect from one's aura contacting the glass will determine a person's aura type.


 * If the volume of the water changes, the user is an Enhancer.
 * If the taste of the water changes, the user is a Transmuter.
 * If impurities appear in the water, the user is a Conjurer.
 * If the color of the water changes, the user is an Emitter.
 * If the leaf moves on the water's surface, the user is a Manipulator.
 * If a completely different change appears, the user is a Specialist'.

It is best to base a Nen ability on one's individual aura type. Though it is possible for one to develop abilities outside of his primary aura type, one is typically less proficient at using those abilities. By creating an ability that one isn't suited for, one risks stagnating their potential by overloading their capacity for using Nen —something Hisoka calls "Memory Overload."

Hisoka also claims that he is able to judge a person's Nen type based on their personalities. According to him, all people of one aura type are generally of the same personality type. However, he states that this method is similar to trying to find someone's star signs or blood type just from personality analysis —it's not always correct. According to his theory:


 * Enhancers are determined and simple. Most of them never lie and hide nothing. Their words and actions are often dominated by their feelings. They are generally very selfish and focused on their goals.
 * Transmuters are whimsical liars. Transmutation users have unique attitudes, and many are regarded as weirdos or cheaters. They rarely reveal their true intentions.
 * Conjurers are typically high-strung. They are often on guard as to be overly cautious. They are very observant and rarely fall into the traps. Being able to analyze things calmly is the strength of Conjurers.
 * Emitters are impatient and not detail-oriented. Many of them are quick-tempered and hot-blooded. They resemble the Enhancers in building their impulsivity, but the difference with them, they probably tend to calm down and forget easier.
 * Manipulators are logical people who advance at their own pace. They are all for arguments and tend to want to keep their families and loved ones safe. On the other hand, when it comes to pursuing their own goals, they do not listen to what others might have to say about it.
 * Specialists are individualistic and charismatic. They will tell you anything important on them, and refrain from being close friends. But, because of their natural charisma that draws others, they are always surrounded by many people.



There are numerical approximations given by the manga to indicate just exactly how efficient one would be at using aura abilities that one is not born into. Starting at one's own aura type, one has the potential to be 100% efficient at using abilities based in that category alone. Then looking at the category chart (see right), one has the potential to be 80% efficient at using aura types adjacent to your primary type, 40% efficient at the opposite or farthest category, and 60% efficient in the two remaining categories. Specialization is typically unusable for non-Specialists because it is impossible to partially use; one either can or can't use Specialist abilities. However, Conjurers and Manipulators have 1% efficiency potential for Specialization due to being adjacent to it.