One of the things that should be remembered right now is this: if a narcissist has the ability to be good and kind, there is a big chance that the person is a not a narcissist, to begin with. It should be remembered that narcissists are abusive people. They have the ability to harm other people emotionally and mentally.
They do this in order to improve their overall well-being. They do it so they can begin to feel better about themselves. They want to feel that they are better than other people and when someone shows them that they are not the best, they will do everything in their power to make others suffer.