Illumi Zoldyck

Illumi is the eldest child of Silva and Kikyo and was raised from birth in the art of assassination. He and his father trained Killua to become an elite assassin. At some point during his childhood, he learned Nen. In order to control the development and actions of his younger brother, Illumi inserted a Nen needle into Killua's brain under Silva's order; the needle prompted him to run away from the battles he wasn't certain he could win. Sometime prior to the 287th Hunter Exam, he also established a partnership with Hisoka; however, this partnership is not detailed. About three years prior to the events of the Yorknew City arc, Illumi and his brothers were summoned by their father, who, having just assassinated member #8 of the Phantom Troupe for a price deemed not worthy of the job (the highest compliment he ever gives a target), admonished them to stay away from the Troupe. Following Killua's escape from the Zoldyck manor, Illumi was sent by his mother to watch over his brother at the Hunter Exam.