One thing you'll love about Hunter x Hunter is the balanced power level. Characters are not just powerful for no other reason or didn't come with risk. Some are attained through training and some put their life in the line just to be powerful. So the word overpowered can't be applied in this anime because there are none of them with perfect skill or abilities. I am not sure about the Chimera Ant King. That monster is close to perfection but love beat him and the queen didn't make him immune to poison (LOL).
But there are characters in Hunter x Hunter that has a powerful abilities but because of risk and restrictions, they cant execute it properly. And here are some characters' ability that have an infinite potential but nerfed with great risks.
Chain Jail and Emperor Time
Kurapika
Thats right! Two powerful abilities possess by the same person. If I include Judgement Chain which is also a broken ability it will make three. But since it can only be used under Emperor Time state I will just put it under its category.
Chain Jail is a powerful conjurer ability which transform Kurapika's aura into chains. And whoever captured in this ability can't escape using only his brute force since Zetsu can stop the flow of aura which makes them incapable of using nen. It is a terrifying ability Kurapika possess that even the physically strongest among the member of Phantom Troupes cant escape. Additionally enhanced by Emperor Time and Combo Skill of Judgement Chain, Kurapika makes the most dangerous character that villain must be terrified off. However, this skill is accompanied with dangerous risk. He can only use this ability towards the member of Phantom Troupes. If he happens to use it on other people, he will die because of conditions he set on himself to increase the power and effectiveness of this skill. It may be useless after the defeat of Phantom Troupes but his other skills are still there especially his ability.
Emperor Time. This ability is really scary. He can activate Emperor Time when his Eyes turn into scarlet. During this duration, he gain mastery on all category of Nen and give significant boost on all of his skill. Another bonus to this ability is the granted access to Judgement Chain ability which just like I said one of the most dangerous and powerful skill in this series. It will pierce and wrap the victim's heart and if he/she didn't follow the two conditions set by the user, it will crush it and eventually kill its victim. Emperor Time might be powerful ability but the toll that it takes to the user's body is very risky. Kurapika can only use this at 3 hours maximum per day. After that, he will become feverish and fatigue will wear down his body which can last up to several days. It is very dangerous in long term battle since he will become vulnerable after he uses this ability.
Skill Hunter
Chrollo Lucilfer
This ability might be the strongest and useful ability in Hunter x Hunter if Kurapika didn't put conditions on Chrollo. This ability can steal other people's skill or ability. The skills are stored in Chrollo's conjured book named Bandit's Secret and he can willfully use any type of skill and ability he stole from other people. Just imagine if he stole Kurapika's Chain Jail, Neteros' 100-Type Guanyin Bodhisattva or even Nanika's Wish Granting Ability. He can be one of the strongest character of the whole series.
Chrollo's skill might sound convenient and powerful, but it is also one of the hardest skill to activate. Not to mention very risky especially when faced to stronger enemies. To make his ability work he needs to fulfill 3 requirements within an hour. First he must see the skill/ability in action. Then he must ask question about their power and they must answer. And lastly, they must touch the Bandit's Secret using their hands. It may work on stupid and weaker persons but for some who is experienced and wary, he may have a hard time.
Zero Hand and Rose
Isaac Netero
Zero Hand is the ultimate skill of 100-Type Guanyin Bodhisattva. From the mouth of Guanyin Statue, a destructive light fired unto the enemies. It is very powerful that may even kill other strong characters in the series when it hits. Well the price to pay for this destructive attack of also immeasurable. It takes a lot of time to fully charged leaving the user in great risk. And if it fired successfully, it drains a lot of stamina from the user and that even makes Netero much smaller and looks much older because of so much energy drained from him.
Rose is a type of skill can't be spammed in the battle. It is a one time sacrificial attack developed by Netero himself. It is the most dangerous attack that we may even call it forbidden. In exchange of users life, he can create a destructive bombs that if it used in the cities it can wipe out the entire population not just because of destructive power but also the poison after effects. It is a strong type of poison that even kill Meruem.
Wish Granting
Nanika
Nanika is an unknown being hidden inside Alluka's body. Being a child from Zoldyck family, they kept it hidden and the fact on how Nanika possess Alluka is still a mystery. This child makes the whole family scared because of the ability it possess. If Nanika ask you 3 request you must fulfill it completely and she will grant you 1 wish. But if you've failed to give what she wants, you'll get killed. It is a high risk high return skill and even the whole family avoid contact with their child. The only one who can understand Nanika's power is Killua. This power is very dangerous especially if bad people get a hand of Nanika's wish. But they must be prepared for Nanika's requests.
I didn't expect that this article will be this long. And since there are some characters that I didn't put here yet, I decided to make a Part 2 article of this. Hunter x Hunter power balance is amazing that even the powerful characters can be defeated by just discovering their weakness. Skill is very important.
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