|1999 - 2011|
|Debut:||Chapter 6; Episode 6 (1999); Episode 3 (2011)|
|Japanese VA:||Kanako Mitsuhashi (1999); Mariya Ise (2011)|
|Other VA:||Annika Odegard (English)|
|Age:||12 (as of 2000)|
|Eye Color:|| Deep teal (1999); |
Royal blue (2011)
|Relative(s):||The Zoldyck Family|
|Nen:||Lighning Palm; Thunderbolt; Godspeed|
Killua is slender and fairly tall for a boy his age with messy short silver hair. His style of dressing has changed little over the course of the story. He usually wears sports shoes, shorts, an undershirt and a T-shirt, which can have long sleeves, short sleeves, or no sleeves at all. He also wears long pants on occasion. In the beginning of the story he carried a skateboard with him but later on it was no longer seen.
Killua is a whimsical liar. His personality is similar to that of a cat--unpredictable. Due to the unusual background in which he grew up he is quite cold-hearted, but generally he is a somewhat shy boy. He has a quick, analytical mind capable of making sensible decisions. However, sometimes he also acts on impulse to defend his reputation and pride. Killua strongly dislikes the practice of assassination, which even up until now is still casting a shadow over him. The salient features of his personality are:
- Ruthless: When Killua switches into assassin mode he eliminates his enemies without mercy. In the beginning of the story he even killed randomly when he was stirred up.
- Carefree: His words and actions are typical of a happy-go-lucky young boy. He once joked that he would capture his family after becoming a Hunter.
- Careful and Rational: Killua is careful and can make wise dicisions and act matter-of-factly in dire situations. But because of Illumi's needle in his head, sometimes he became overcareful and gave up quickly.
- Observant and Creative: Killua has an eye for detail and is capable of easily coming up with clever ways to defeat his opponents.
Born as the 3rd son of Silva, the current head of the infamous Zoldyck Family, and his wife Kikyo, Killua was trained from a very young age in assassination by his father and eldest brother Illumi, who has a twisted love for him. He quickly showed his immense talent mastering a number of advanced assassination techniques and reaching the renowned Floor 200 of the Heavens Arena at the age of 8. As a result he is loved by most of the residents of the Zoldyck estate, especially his mother, and was designated to be the heir to the family business. In order to protect Killua and to control his development, Illumi even secretly implanted a needle in Killua's brain, forcing him to flee from the battles he was not sure he could win. However, Killua, not wanting to be treated like a puppet, rebels against his parents and runs away from home to take the 287th Hunter Exam, injuring his mother and 2nd brother Milluki in the process.
287th Hunter Exam arc
Zoldyck Family arc
Heavens Arena arcAfter Kurapika and Leorio have left, Killua tells Gon that Hisoka is so much stronger than him that it is very hard to return the badge #44 in 6 months. As they have very little money, Killua asks Gon to go with him to the Heavens Arena to earn some through fighting. It turns out he was forced to fight here at the age of 6 by his father and managed to reach Floor 200 in 2 years. Seeing Gon's nervousness before his 1st match, Killua tells him he only needs to push the opponent with all his strength, which Gon does and thereby sending his opponent flying instantly. Killua also knocks out his opponent with a single chop to the neck. They are then sent straight to Floor 50, where they meet and befriend a boy about their age named Zushi, who is also a newcomer and practices Shingen-ryu, and his master Wing. Soon, Killua is required to fight his new friend. With vastly superior speed and strength, he easily knocks Zushi down multiple times but he keeps getting up. Knowing he has no chance against Killua physically, Zushi decides to use Ren. However, when he has just started it, forcing Killua to retreat, Wing in the stands angrily shouts out his name. Zushi is startled and immediately stops his Ren. Killua eventually wins by TKO, but he is baffled by Zushi's ability to take even an all-out punch of his without being knocked out. After the match, he overhears Wing telling Zushi that he cannot use Ren in combat yet, and that his goal must not be to win a single match but to reach the top of the arena. Killua thus tells Gon he is going to change his plan--instead of fighting only for money, now he wants to get to the top to know what Ren is. A few days later, not wanting to wait until they reach Floor 200, he and Gon find and ask Zushi about Ren. Zushi shares with them his little knowledge of Nen, but it is not of any help to Killua. Wing interrupts their conversation and tells him that little knowledge is a dangerous thing. Killua however insists on learning about Nen, saying his brother uses it. Wing thus invites the 2 kids to his apartment and teaches them the fake Nen and the Fake Fundamentals. Even though his demonstration of Nen is real, Killua knows there is more to Zushi's toughness than what Wing taught them. Several more days pass and he and Gon both reach Floor 200 with ease. However Hisoka suddenly appears and prevents them from registering for a fight on this floor by setting up an aura barrier. Wing then shows up and tells them they will die if they try to get past it. He also admits he lied to them and agrees to teach them the real Nen.
In Wing's apartment, Gon and Killua have their aura nodes forcibly opened by him. They can instantly retain their auras, astonishing Wing. They then return to Floor 200 and overcome Hisoka's barrier before deadline with no problem. However, when they are filling out their registration forms, they are approached and sized up by Gido, Riehlvelt and Sadaso, the handicapped trio who go after rookies on this floor. Gon is immediately scheduled to fight Gido the next day, on March 11th. Due to his stubborness and recklessness, not only does he lose, his right arm is also broken and will be put in a cast for 2 months. Wing forbids him to practice Nen until he has fully recovered. He invites Killua to train with Zushi in the meantime, but he declines. He then keeps practicing the fake Nen with Gon.
1 month later, Killua buys 2 tickets for the match between Hisoka and Kastro, a popular fighter on Floor 200, and asks Gon to watch it with him. But he has to go alone due to Wing's forbiddance. He tries to approach Kastro secretly to see how strong he is, but is detected and surprised by him. They then have a fairly friendly conversation. Shortly afterwards Kastro is killed by Hisoka. Near the middle of May, after Gon has his cast removed, Killua and him resume their Nen training. Wing explains to them how Hisoka used In to defeat Kastro and tells them they must master Gyo. Killua and Gon want to wait until June 9th and 10th, the latest days possible for them. However, in the evening of the same day, Riehlvelt and Sadaso kidnap Zushi. To save him, Killua agrees to let Sadaso win a match on May 29th. Unbeknown to him, Gido also uses one of Zushi's shoes to blackmail Gon into having a match with Sadaso on May 30th.
The next day, knowing what the trio did to Gon, Killua is furious. Thus, he shows Wing that he has mastered Gyo overnight to get the permission to fight earlier. Gon also does the same. On May 29th, he infiltrates Sadaso's locker room 10 minutes before their match and threatens at knifepoint to kill him if he tries another dirty trick. Fearing for his life, Sadaso leaves the arena and tells his 2 associates by phone about how dangerous Killua is, allowing him to win by default. A few days later, he enters Gido and Riehlvelt's room unnoticed and threatens to kill them as well if they do not respect the rules. Frightened, they decide to play it fair.
On June 4th, Killua has a match against Riehlvelt. After he easily catches Riehlvelt's whips, Riehlvelt switches on the concealed electroshock devices in them, sending two 1,000,000 volt currents through his body. Killua however can withstand the currents. He then yanks the whips, throwing Riehlvelt high in the air. As Riehlvelt falls down, he catches him with the electroshock devices still on, giving him a dose of his own medicine. Riehlvelt passes out instantly and loses. He is also scheduled to fight Gido on June 9th, but because Gido withdrew after losing to Gon on June 4th, he wins by default again. After that, through Water Divination, he knows he is a Transmuter. On July 9th, when he is able to make plain water as sweet as honey using his Ren, Wing declares that he, together with Gon, has passed the hidden Hunter exam. Following Gon's defeat by Hisoka on the 10th, he and Gon leave the arena for Whale Island to visit Gon's relatives.
Yorknew City arc
Greed Island arc
Chimera Ant arc
New Hunter Chairman Election arc
Killua was tortured and trained in assassination from a very young age; therefore he possesses excellent physical abilities despite his slender build. For example, he can jump higher than Gon, a talented Enhancer, can, and even without using Nen he can push open the 3rd gate of the Testing Gate, weighing 16 tons in total. He is also immune to numerous types of poisons and toxins, and has great endurance and high tolerances to pain and electricity.
- Killua ranked first in all of the 3 character popularity polls that have been conducted so far by Weekly Shounen Jump.
- He likes playing video games and eating snacks--most of the 200 million Jenny of prize money he earned in the Heavens Arena at the age of 8 was spent on snacks.