Does only psychopaths and sociopaths have no conscience or can just a plain narcissist too?

Not only psychopaths and sociopaths lack a conscience, but narcissists can as well. However, it's important to understand that not all narcissists lack a conscience, and not all individuals who lack a conscience are narcissists. Psychopathy and sociopathy are characterized by a lack of empathy, remorse, and guilt, while narcissism is characterized by an inflated sense of self-importance, a need for admiration, and a lack of empathy. While there is some overlap between these traits, they are not synonymous.