DISCLAIMER: While I have had college level courses in developmental and abnormal psychology I am not licensed in the field. This information comes primarily from the following sources:

http://en.wikipedia.org/wiki/Narcissism
http://en.wikipedia.org/wiki/Narcissistic_rage
http://en.wikipedia.org/wiki/Malignant_narcissism

Narcissists

Narcissists strive to make themselves look and feel positive, special, successful, and important. They are often perfectionists with a grandiose self-image who require being the center of attention. They therefore create situations where they will receive the attention they crave and frequently pretend to be more important than they truly are. They often claim to be an expert at many things. Narcissists tend to brag subtly but persistently about their own achievements, and make them out to be more impressive than they really are. They exhibit an obvious self-focus in interpersonal exchanges.

If a perceived state of perfection isn’t reached it can lead to guilt, shame, anger, or anxiety because the narcissist believes he will lose the imagined love and admiration from other people if he isn’t perfect. That said, narcissists tend to be vulnerable to shame rather than guilt: shame is a violation of cultural or social values while guilt feelings arise from violations of one’s internal values. Narcissists tend to blame a situation rather than self for failure and they deny their own culpability while blaming others for it. They are hypersensitive to any slights or imagined insults. A narcissistic person flatters those who admire and affirm him, and detests those who do not. They expect unreasonably favorable treatment and when it is not forthcoming they perceive it as an attack on their superiority. Defiance of a narcissist’s will can trigger narcissistic rage (more on that later).

Narcissists typically have problems with empathy and sustaining satisfying relationships. A narcissist will use other people without considering the cost to them of doing so, and will debase or degrade others to increase his own sense of self-worth. He will use contempt to minimize other people. The narcissist exploits others without regard for their feelings or interests; often the exploited person is in a position where resistance is difficult or impossible. Narcissists do not recognize that others are separate: not extensions of themselves. Others either exist to meet the narcissist’s needs or may as well not exist at all. Those who meet the needs of the narcissist are treated as if they are part of the narcissist and are expected to live up to those expectations.

Narcissistic Rage

When things are not going his way — when a narcissist is not getting the responses he expected and needed — he goes into a rage in an attempt to create conflict and alleviate his pain and suffering. While conflict and alleviation of pain may seem at odds, a narcissist needs to totally control his environment, and creating a conflict allows him to do so. It allows him to transform himself from a passive victim into an active player while rebuilding his false sense of self-worth. It also restores a sense of safety and power, because the rage is intended to destroy the threat.

A narcissistic rage feeds the narcissist’s need to right perceived wrongs and seek revenge. Narcissistic rages always center on revenge, and will endure even after the threat is gone. To the narcissist, the rage is directed towards the person that they feel has slighted them; to other people, the rage is incoherent and unjust. This rage impairs their cognition, therefore impairing their judgment. During the rage they are prone to shouting, fact distortion, and making groundless accusations.

Malignant Narcissism

Malignant narcissism lends itself to gratification in intellectual and other positive pursuits. The malignant narcissist desires unlimited power and will attempt to make full use of their capabilities. According to Otto Kernberg, malignant narcissists are said to be capable of developing “some identification with other powerful idealized figures as part of a cohesive ‘gang’.”

The malignant narcissist derives high levels of psychological gratification from accomplishments over time, which serves to worsen the disorder. Because the malignant narcissist becomes more involved in psychological gratification, he is apt to develop antisocial, paranoid, and schizoid personality disorders. Social psychologist Erich Fromm first coined the term malignant narcissism in 1964, describing it as a “severe mental sickness” representing “the quintessence of evil.” He characterized the condition as “the most severe pathology and the root of the most vicious destructiveness and inhumanity.” Malignant narcissism is highlighted as a key area when it comes to the study of mass, sexual, and serial murder.