Hunter x Hunter - episode 12 - 14 Jan, 2000

Killua stops trying to take the ball from Netero because his killer instincts are surfacing. Anita escapes her handlers and attacks Killua, who comes close to killing Anita, but lets her live because otherwise Gon would get mad at him. Gon is never able to get the ball, but makes Netero use his left leg and both hands once, and is satisfied. (Source: Wikipedia) Hunter Exam arc: (12/31)