Season 2 Episode 14 - A Necessary Evil

Velasca manages to come back from the dead as she manages to eat some ambrosia and the only thing on her mind is revenge. She wants to kill Gabrielle and anyone who opposes her, because she is now a god this wont be to hard. Xena and Gabrielle have to think of a way to defeat her so they need a God who is willing to help, the only person they can think of is Callisto, she is not a god but she is immortal which will make things a lot easier. They give her the incentive that Velasca has ambrosia and if she defeats her then she has a shoot at getting it. He agrees but betrays Xena and Gabrielle and teams up with Velasca, fortunately Xena fought this would happen and she cleverly manipulates it so that Velasca does not trust Callisto and they become enemies.

The next time Xena and Gabrielle met Velasca, Callisto and Velasca have a massive fight to get the ambrosia, Callisto wins but Xena manages to trap both Velasca and Callisto in a pit of lave forever, hopefully.