"She was trying to, but every time she got close enough, a head would get between her and it, and she would have to cut it off before it could bite her with its poison fangs.
But the boy knew from his evil magic lessons that a hydra could only grow new heads from clean stumps, so he began using the magic that the sorcerer had taught him to snap the hydra's necks. Because even magic traditionally used for evil can do good, in the right hands."