When a fight ends, there is a risk that you will run wild and continue fighting after the opposition is down.
At the end of a fight, make a roll based on the number of Magic points you have spent this session vs. your Powers. If you fail you lose control and enter a killing spree.
When this occurs, you go wild with your lust for violence; you start attacking defeated enemies, bystanders, your friends or even yourself, in that order. If confronted, people can try to make Seduction rolls against a difficulty equal to your Powers; success brings you out of the killing spree. Otherwise, you are out of control for one sequence per point of negative outcome.