Narcissist Or Non-Narcissist

Narcissists are happy when they get what they want and when they feel like they're in control, regardless of how others around them are feeling, even if they were the cause of another's distress; often, they feel happy BECAUSE they caused another distress, and therefore feel "superior" or "vindicated". Non-narcissists don't desire control over others, and are not happy when those around them are feeling badly; especially those close to them, and especially if they were the cause of it, whether it was intended or completely unintended.

Narcissists are much more concerned about defending themselves and deflecting blame than they are about another person's welfare; non-narcissists are much more concerned about another person's welfare than "who's to blame".

Narcissists will attack another person when they feel any hint of challenge, embarrassment, or criticism, and feel perfectly entitled and justified in their aggression and hostility toward another human being- they feel justified in "using a cannon to swat a mosquito" and will not stop defending their actions. Non-narcissists will only "attack" in defense, and only after they've been put under enough duress that they've lost their tolerance, or they feel literally threatened, and they'll feel remorse for losing their temper in most cases (not all) regardless of the events that took place.
In other words, a Narcissist will feel perfectly justified in verbally and emotionally attacking a person who didn't agree with them about something big OR small; they don't seem to realize that verbal and emotional attacks are simply wrong, period, no matter what, no matter the situation, and no matter who's "right" or "wrong". A non-narcissist, however, will usually feel remorse for losing their temper and attacking someone even when the person did or said something terrible to them.

Narcissists try to justify everything they do with excuses about what other people do or say. They don't feel remorse or guilt, they feel entitlement, vindication, and justification. Non-narcissists simply don't do that (usually); they know they're responsible for their own actions no matter what other people do or say. When they do slip up and try to justify wrong or mean actions, they feel remorse for THAT, and try to make amends.

Narcissists are concerned about being right, being in control, feeling vindicated, and feeling dominant, regardless of other people's welfare, well-being, and feelings.
Non-narcissists are more concerned about the welfare, well-being, and feelings of others (and themselves) than being "right" or "wrong", who's the boss, whether anyone gets to be in charge, defending themselves, or "vindication".