"Let's begin your training." -Bisky
"Osu!" Silver enthusiastically answered.
Nen is a technique that allows a living being to use and manipulate their own life energy or aura. A person capable of utilizing Nen is colloquially referred to as a "Nen user" while those who cannot go by the designation "non-users".
Because Nen-users can cause devastating damage to those who are non-user, it is considered a dangerous power that is kept hidden from the public at large to maintain balance in society. You are not supposed to learn it yet, but that incident happened.
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. There is a second method though, colloquially called Initiation, it is achieved by forcing the Aura Nodes of the student to open via an influx of aura by performaing hatsu on them. In your case you received your initiation when Charanko failed to fully control his newly awakened nen ability.
While all living things possess aura and all humans are able to master Nen, some excel at its usage more than others. You for an example is an anomaly. A 7 year old who exudes an aura equal to the top nen users at the age of 20.
There are threee basic techniques a nen user must be familiar with.
They are:
• Ten ("Point"): Focus the mind, reflect upon the self, and determine the goal. Ten is the process of keeping the nodes open, but also having aura flow through and around the body rather than away from it. Having a shroud of aura surround the body is the most basic defense against the physical or emotional attacks of another Nen-user.
• Zetsu ("Tongue"): Put it into words. Zetsu stops the flow of aura from their body altogether. By closing all of their aura nodes, the user is able to stop almost all outflow of their aura. Zetsu can also be used to restore vitality, since Nen is fully contained within the body. However, since Zetsu involves shutting off one's aura, it can be dangerous since it leaves the body defenseless against any Nen attack. Even the weakest Nen could do massive damage.
• Ren ("Temper"): Intensify your will. Ren is a direct application of Ten. Since a user is capable of keeping aura from leaking away from the body, it's also possible for them to have more aura around them without having to worry about losing it. Ren focuses on outputting a high amount of aura and keeping it on the body, expanding the size and intensity of it. This increases the user's physical strength and durability and provides a large pool of aura for any advanced techniques or individual skills they decide to use.
Then there are the advanced techniques. Most of them are achieved by using a combination of the basic techniques. Most nen users learn Ten, Zetsu and Ren first before attempting these techniques. The Hatsu, being a nen-user's individual 'skill', is often something that a nen-user will develop gradually over a long period of time.
• Shū is the advanced form of Ten. Shu allows a Nen-user to extend their aura to an object, allowing them to "use" that object as if it were an extension of their own body. For example, one could use Shū to extend their Ten around an object (and not just their body), which would strengthen and protect the object like the way Ren strengthens and protects the body.
• En is an advanced application of Ren and Ten. In Ren, aura usually envelops only a small amount of space around the user's body. En is when one extends their Ren so that their aura extends further than normal, then uses Ten at the same time to give shape to the aura, usually a sphere. Someone using En can feel the shape and movement of anything entering their En-covered area.
• Ken is the advanced version of the basic Ren technique. Ken is a defensive technique where a Nen-user maintains a state of Ren over their entire body, allowing them to defend against attacks from any direction without the need to use Gyō. Ken is as useful as a defensive position, but is tiring to maintain. Additionally, it is not as strong as Gyō on any given part of the body, since it protects the whole body evenly. Because of that, it is used to guard when one wants to be cautious.
• In is an advanced form of Zetsu that can almost completely hide a Nen-user. In can also be used on a Nen-user's Hatsu ability to make it invisible to other nen users. In can be countered by using Gyō on the eyes, or by using the technique En.
• Gyō is a technique where a Nen-user concentrates a larger than normal portion of their aura into one specific body part. This ability to concentrate the aura is known as Gyō. Gyō increases the strength of that one body part, but leaves the rest of your body more vulnerable. Gyō is most often used on the eyes, which allows a Nen-user to see things which would otherwise be hidden by In.
• Kō is the strong form of Gyō, where all of an individual's Nen-energy is concentrated into one particular body part. Zetsu is used to completely stop the flow of Nen in all other parts of the body. This makes that one body part exceptionally powerful, but leaves the rest of the body completely unprotected.
• Ryū ("flow") is the term for real-time use of Gyō (adjustment of aura concentration in various body parts) by a Nen-user in battle. For example, the use of Gyō to increase the amount of Nen in a fist as one strikes with it, to increase damage done; or to increase the amount of Nen in an arm as it is used to block a blow, for extra defense.
Hatsu is the release of one's aura so it can be projected to carry out a certain function. In essence, the Hatsu is a special and unique ability that one creates. A good Hatsu should reflect a Nen-user's own character; one can never truly master Nen if they only copy other people's abilities. Hatsu has several different categories, and the Nen of each user is aligned with a specific category. Upon learning their affinity, a user can set about learning to apply Nen in a unique way that suits their personality, which can develop into a unique skill. A user may also have the ability to use more than one Nen ability, but they may never be able to change their Hatsu-type. However, even though a user may be able to use more than one Hatsu, they can only be adequate at the Hatsu adjacent to his primary Hatsu. Or if they are hybrid type hatsu, thay can use efficiently two types of Hatsu but is further penalized on the adjacent Hatsus.
Although everyone's Hatsu is different and unique, Hatsu can be divided into five rough types and a sixth type for anything that does not fit into the five.
Types Of Hatsu
Enhancement
Enhancement is basically the ability to use nen to increase the efficiency (strengthen) of an object or body. Therefore, Enhancers are able to greatly increase their physical attack and defense, and are best suited for close-melee combat.
Enhancement is the most well-balanced category, allowing users to spread themselves evenly between offense and defense and become very strong using only simple abilities. Examples of more complex Enhancement abilities include enhancing a person's ability to repair themselves, which is basically the equivalent of a healing-ability.
Emission
Emission means that a user is capable of controlling the deployment of their aura while separating it from their body. Nen usually loses power very quickly when it is separated from the source-body, but strong Emitters can separate their aura from their body for long-periods of time and still be able to maintain it.
An application of this is the ability to throw giant nen balls.
Emission abilities are commonly mistaken for Conjuration abilities. The two, however, are fundamentally different. Objects created by Emitters are made of pure aura, believed to be invisible to normal people, and requires Manipulation skills to control.
Transmutation
Transmutation means a user can change the properties of their nen, usually so that it mimics something else. Like emission, things created via transmutation are still pure nen. A simple way of thinking about it would be that transmutation allows your nen to mimic properties of a substance, whereas conjuration allows you to change your nen into actual material.
Nen can copy properties of real things, for example, one could use his nen to copy the properties of electricity. Transmuters can also give their nen properties that don't necessarily mimic real things; "Bungee Gum" copies and combines the properties of rubber and gum. Transmuted substances are invisible to normal people (i.e. those who are not able to use nen).
Manipulation
Manipulation is the ability to control other people or other non-living material. Abilities belonging to Manipulators tend to be more complex, and generally require certain conditions to be met before the user is able to control the target object.
Conjuration (Materialization)
Conjuration is the ability to create a physical, independent, material object out of nen. Once a nen-user has mastered the conjuration of a certain object, they can conjure it and dispel it in an instant, whenever they want. It is believed that conjuration is the only way in which nen can create things which ordinary people (who don't use nen) can see and touch. However the use of In can hide an object materialized by nen from an experienced nen-user.
Like Manipulation nen, conditions can be set into conjured objects to make them stronger. For example, one could be able to materialize a perfect copy of any non-living object that he touches. However, all of his materialized objects will automatically disappear after 24 hours.
Like Manipulation, Conjuration abilities tend to be very specific, complex, and conditional.
Specialization
Specialization is anything that doesn't belong into the other five categories. This is the most vague Hatsu-category. Specialization examples have ranged from being able to utilize 100% of the five standard Nen types, another with the ability to steal other's skills, and one that could even predict the future.
Specialists often have some of the most strict conditions on them due to their often powerful nature. Most needing to fulfil several conditions before it can be used.
One should also note that it is possible to become a Specialist later in life, although this is more likely for Manipulators or Conjurers.
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Thank you wikipedia, HunterXHunterFandom and Hunters world site owners for your contribution. And also thank you to the Man, the Myth, the legend, the author himself, Yoshishiro Togashi.