Killua Zoldyck

A twelve-year-old assassin who leaves his lethal family behind to find friendship and strength alongside Gon Freecss.

Killua Zoldyck is a skilled and rebellious twelve-year-old boy from the world's most notorious assassin family, the Zoldyck family. Bored and tired of killing, he meets Gon Freecss during the first portion of an examination for people who wish to become "Hunters." Aiming to escape his family and his past, Killua joins Gon's quest to find his missing father, and they work together to become stronger fighters. As the story goes on, they become inseparable friends. Created by Yoshihiro Togashi as one of the first characters for the series, Killua was designed specifically to fill the role of Gon's friend, with their relationship inspired by the protagonist's personality and young age.

Quick Facts

Series: Hunter × Hunter
First: Hunter × Hunter manga chapter 6: "The First Phase Begins, Part 2" (1998)
Creator: Yoshihiro Togashi

Lore & Background

Killua is a member of the Zoldyck Family, trained since birth as an assassin with extreme tolerance for poison, electricity, and pain. Initially introduced as a mischievous child during the Hunters' examination, he displays ruthlessness and a deadly aptitude for killing. However, conflicting with this predisposition is his unyielding loyalty to new friends, whom he puts before himself without complaint. Although set to be one of the best assassins his family has ever produced, Killua fails his first Hunter Exam attempt after killing an opponent under his elder brother Illumi's influence. He returns the following year, earning his license by eliminating all other applicants in the very first trial. His Nen type is Transmutation, allowing him to alter his aura into electricity, a technique aided by his body's resistance developed through violent upbringing.

Reader's Guide

To understand Killua's evolution, note his transition from a "one-man killing machine" to a devoted friend. His combat style relies on Transmutation Nen, specifically converting aura into electricity to enhance physical capabilities like speed and strength. Key turning points include failing the first Hunter Exam due to Illumi's manipulation, re-taking it successfully by clearing all applicants in one trial, and developing Godspeed during the Greed Island arc.

In the Chimera Ant arc, a critical moment occurs when he removes the needle Illumi placed in his brain, overcoming his fear of losing Gon. Later, he demonstrates immense bravery by freeing Alluka to save Gon's life, defying his family once more. For fans, his voice acting history is notable: Kanako Mitsuhashi and Mariya Ise voiced him in Japanese adaptations (1999 and 2011 respectively), while Annika Odegard and Cristina Vee handled the English dubs.

Did You Know?

In the 1999 anime adaptation, the staff originally planned a dark ending where an adult Killua returned to kill Gon, but Togashi rejected this scenario.
During the Greed Island arc, Killua was forced to use yoyos as weapons because his hands were wounded in battle.
Killua's voice actress for the 2011 series, Mariya Ise, received positive feedback from creator Yoshihiro Togashi herself on Twitter for portraying Killua's sensitive side.