What comes to mind is motive. What is the motive behind every move the narcissist makes? Most of us humans don't go about having ulterior motives by what we say and do. We have good intent in our relationships but not the narc , far from the truth.
Motive is defined as a reason for doing something, especially one that is hidden or not obvious (overt or covert-take your pick) or something (such as a need or desire) that causes a person to act.
Motive is one of the engines a narcissist uses to propel their sadistic and malicious ways. What is their need or desire behind their motive...to destroy you as a whole person without being guilty of the crime.
Evil motives are behind everything the narc says and does. Distortion plays a big part of it. They want you to put on glasses that you were never meant to have. Through their sorcery they operate with these hideous motives to twist and contort our emotions into tangles of ensnared and enmeshed prisoners of their abuse.
They confiscate one's mind so they can remove all sound reasoning to get to the heart. A diversion tactic to allow for debilitating emotional duress leaving a person feeling helpless and frozen.
In the beginning you may be hoodwinked to believe their motives are very honorable or virtuous. This is just an act so your guard is let down. So a narcissist will hide behind good motives when in fact they are setting their target up to display their true motives which is utter destruction of your mind, body and soul.