Narcissists are often vindictive and they often stalk and harass.
To Frighten Them Narcissists live in a state of constant rage, repressed aggression, envy and hatred. They firmly believe that everyone is like them. As a result, they are paranoid, suspicious, scared and erratic. Frightening the narcissist is a powerful behaviour modification tool. If sufficiently deterred the narcissist promptly disengages, gives up everything he was fighting for and sometimes make amends.