The dubiously clever foes and aloof "helpers" in the world of Hunter X Hunter.
When you're up against this guy, you should be.
- Chrollo Lucilfer, leader of the Phantom Troupe is a handsome, charismatic young man who masterminds elaborate heists and mass murders, only to get bored of the objects he obtains and sells them away again. Coming to the mafia-ruled Yorknew City, Chrollo masterminds the heist of the century where the Spiders infiltrate the mob and steal all the items from a high profile auction while Chrollo targets and steals the power of one mob leader's daughter. Completely outwitting the mob, Chrollo learns there is a contract on his head from the Twelve Godfathers and instantly hires different members of the same assassin family to target the Godfathers before having the Spiders fake their deaths and escape completely free. Chrollo also deeply values the other members of the Troupe, offering the lives of multiple mafia soldiers as a "requiem" for the fallen Uvogin, and when he faces off with the ruthless killer Hisoka, he also shows what a brilliant tactician and combatant he truly is by completely outplaying and seemingly killing the skilled fighter. A charming, philosophical man who freely admits he places no value on his own life, Chrollo is one of the most memorable villains in all of Hunter x Hunter.
- Hisoka Morrow, the feared "hunter magician", is the most Recurring Character throughout the series aside from the leads, often acting as an antagonist, or an infrequent ally to them. A brilliant fighter, skilled illusionist, and a psychotic murderer who would even kill dead people if science would let him, Hisoka develops a particular interest in Gon and Killua (to an unsettling degree), so he serves as a Stealth Mentor / Trickster Mentor to the boys while facing them as an enemy, and the main reason he's not killed them yet is because he wants them to grow stronger so that he can get the best possible fight with them before finally doing so. He was also a member of the Phantom Troupe for a time, but he only joined so he could fight the above-mentioned Chrollo Lucilfer. Less a true villain and more an adrenaline junkie who will do anything to get or cultivate his fighting/entertainment fix, Hisoka seldom does anything that's too bad or even illegal, and when not "entertaining" himself he seems quite capable of functioning normally in society, leaving ordinary people to their own business. A charmingly affable sociopath with homicidal urges and sexually deviant tendencies, Hisoka is best defined as an amoral Chaotic Neutral party, every bit as likely to help you as he is to kill you.
- Isaac Netero, Chairman of the Hunter Association, seems to be a jolly old man who uses this as an act to test the participants while running the death games of the Hunter Exams. Happily setting up deadly tournament matches to further test the participants, Netero later reveals he is the finest warrior in all humanity. Drawing the Chimera Ant King Meruem into a fight by offering his name, Netero ends the battle by a suicide to detonate the Poor Man's Rose bomb inside himself, assuring Meruem's end by poison to demonstrate the true malice inside human hearts.
- Killua Zoldyck is a shrewd and competent young boy, as well as the middle child of the Zoldyck family. Having been raised since birth to become a great assassin and future head of the household, Killua enters the Hunter Exam, where he meets his best friend Gon Freecs. His experiences with Gon, Kurapika, and Leorio mold Killua into someone who wishes to break free from his family's expectations while still retaining his ruthlessness. Said ruthlessness is displayed when he threatens to kill someone for forcing him and Gon to surrender a fight. Killua is intelligent enough anticipate how his opponents will try to attack him and is good at adapting to opposition. These skills are put to great use, especially when escorting his beloved younger sibling Alluka to heal Gon after a dangerous mission left him hospitalized. After the conclusion of the 13th Chairman Election, Killua chooses to live a peaceful life with Alluka, telling Gon to call him should he ever be needed.
- Silva Zoldyck, head of the Zoldyck family and father of Killua, is a genius assassin who runs his family in a bizarre manner that he nevertheless feels is best for them. Having completed countless assassinations, including that of one of the feared Phantom Troupe, Silva managed to survive a battle with their leader Chrollo Lucilfer. Upon seeing Killua's independence, Silva gives him a supposed freedom as manipulation in hopes it will lead Killua back to the Zoldycks one day. Later facing Chrollo again, Silva shows an exceptional synergy with his father Zeno, utilizing tactics to be able to nearly kill Chrollo himself.
- Pakunoda, one of the Phantom Troupe, is one of the founding members and uncritically loyal to the Troupe and its leader Chrollo Lucilfer. Paku assists in Chrollo's heist at Meteor City, later helping to track and trap Gon and Killua while staying ahead of the Mafia before Chrollo is captured and bound by Kurapika's Judgment Chain. Pakunoda then negotiates for his life while accepting a Judgment Chain of her own. To assist Chrollo, Pakunoda uses a secret ability to transplant her memories to the Troupe, giving them a way to save Chrollo while giving her life.
- Razor is one of the developers of Greed Island and a friend of Ging Freecs. Recruited by Ging after being saved from death row, Razor was tasked with giving his son Gon the fight of his life. He does this via a deadly game of dodgeball, where his throws are strong enough to kill his opponents. Razor demonstrates a keen intellect by being able to adapt to the other team's strategies and mindsets after understanding how they work. Towards the end of the match, Razor bumps Gon's final attack back at him, having learned that he wouldn't want to dodge since that's not how he wants to win. When Razor loses anyway, he takes his defeat in stride, even telling Gon about how he met Ging, respecting the heroes for their victory over him.
- Meruem is the Chimera Ant King and one of the most dangerous villains to be faced. Shortly after being born, he and his Royal Guards occupy a palace where he decides to have countless humans kidnapped to be converted into Chimera Ants for his conquest. In the meantime, he defeats and kills the champions of several board games before being shown a new perspective from one named Komugi. His time with Komugi grants Meruem the desire to save human society from its own flaws. After surviving his battle against Isaac Netero, Meruem pardons his Royal Guard Shaiapouf for keeping Komugi's memory a secret from him. Shortly after learning that he will succumb to radiation poisoning, Meruem swallows his pride and spends his final moments with Komugi, dying together with her.
- Neferpitou, aka "Pitou", is one of the Chimera Ant royal guards and Meruem's most reliable ally. After reading a book on how the brain functions, Pitou easily learns how Nen works by getting the information out of Pokkle. Upon killing Kite, Pitou creates a Nen ability that can control the body to train other Chimera Ants. When Meruem seizes a castle to act as his base of operations, Pitou uses their En to track any intruders, only briefly switching with Shaiapouf to heal Meruem's self-inflicted injury. Preferring to protect Meruem's personal desires, Pitou swallows their pride to guard Komugi, who Meruem grew attached to. Even after Gon's Deadly Upgrade smashed their head, Pitou's Terpsichora ability allowed them to keep fighting, dismembering Gon and forcing him to incapacitate himself to completely destroy their body.
- Menthuthuyoupi, aka "Youpi", is one of Meruem's royal guards who acts as his shield. During his fight with the heroes, he learns how to control his anger to the point where his gives his enemies fake openings in order to attack them. Eventually, Youpi figures out how his opponents' abilities function and corners them, forcing Knuckle to surrender in exchange for their lives. When Meruem is dying from the blast of the Miniature Rose, Youpi demonstrates complete mastery of his bodily workings and liquifies himself to feed the king. Not caring about the safety of his own life, Youpi proves to be adaptable and loyal when the going gets though.
- Pariston Hill, the "Rat" of the Zodiac is an incorrigible hindrance to whomever the Chairman might be. Having always opposed Isaac Netero, Pariston announces his candidacy for the Chairmanship just to keep the others on their toes and enjoy himself. Constantly playing the rules to his benefit and quick to play the crowd, Pariston uses the chance to take thousands of Chimera Ant cocoons for himself before winning the election and promptly resigning in favor of the straitlaced Cheadle Yorkshire. Revealing how much he misses Netero, Pariston declares his intent to always be there to hinder and test the Chairman with a vow that if she ever makes the Association "boring," he will not hold back the next time.