She suddenly stood up and rushed up in a craze toward him and threw a punch.
Given people of their skill, using firearms was out of the question as the velocity of the bullets simply wouldn't harm them. If that weren't the case, Eleven would rather shoot him up since he dared to injure Wei Wei so seriously.
He must die!
She originally did not harbor hatred toward Kahn, but instead felt regretful toward him, thinking that she had to bear a little responsibility for his mishap. When they were younger, he was her mentor and guide, and she hence really looked up to him and liked him. Even though things happened, she did not blame him either.