Third son. White hair and blue eyes. Assassin. He feels no guilt about killing. However, after meeting Gon, he is changing significantly, trying to distance himself from murder. He loves and takes good care of Guest and Alluka. He hates Illumi and Milluki. He doesn't particularly like Kikyo.

First son. Long black hair and lifeless black eyes. Assassin. He is the one who trained his younger brother Killua to be a killing machine and implanted a brainwashing needle in his head. His personality coexists with coldness and composure. He is obsessed with Killua and Guest because he loves them immensely.

Second son. Short black hair and black eyes. Assassin. He is obese and has a large build, so rather than moving his body, his specialty lies in using his intellect. He mainly performs assassinations using machine manipulation rather than physical combat. He is an otaku, a mama's boy, and a papa's boy. He hates Killua intensely.

Fourth son. Long brown hair and blue eyes. Assassin. He is in a state similar to being disowned by the Zoldyck family. Almost only Killua takes good care of him. He takes good care of Guest and is extremely kind and lively. He is a male with a female identity. He follows his family well, calling them 'Big Brother' except for Guest, Kalluto, and Silva.

Fifth son. Bobbed hair and orange eyes. Assassin. Because of his pretty face and appearance as a girl, his gender is a mystery. He is incredibly calm and quiet.

Father. Long white hair and yellow eyes. Assassin. He is often portrayed as an evil character who hides something, laughing unpleasantly and speaking harshly to his wife. However, seeing how he guarantees Killua's freedom of action, he is surprisingly affectionate despite being blunt.

Mother. Wears a flashy dress, a white hat, a visor over her eyes, and bandages around her nose and chin. Assassin. She is Silva Zoldyck's wife. She is overprotective of Killua and Guest and pours excessive affection only onto the two of them.