His elixir of life
Narcissus is very special and You have to treat him like that. To ensure the degree of treatment demanded, he surrounds himself with people who are absolutely loyal to him: his Ego-Extensions. For this he needs a whole bunch of personal lackeys who carry his botty and release him from the annoying burdens of everyday life. And he has a very sure instinct to track those minions down among hundreds of thousands. For example in form of a butler or a personal assistant. If necessary a willing and docile spouse on some children on the drip of his money.
The axle pin of the existence of the Narcissist are his needs. Their satisfaction is his elixir of life. If this spring dries up, the Narcissist suffers from tormenting mental thirst. This condition can be quite deadly. Yes, in a sense, they do actually die of thirst. But at least the loss leads to the immediate deterioration of his health.
A quantum recognition
Now, as You know, everyone is more or less consciously looking for small signs of recognition by other people, but there are two significant differences between a Narcissist and an ordinary mortal: One concerns the quantity. Ordinary people concede a modest amount of recognition. Too much of it is perceived as stressful and avoided. The Narcissist, on the other hand, is something of a psychic equivalent to an alcoholic: like a possessed man he plunges on any pleasurable sip, but is still thirsty after three bottles, because his desire is insatiable.
Value of life, a cost benefit analysis
The second difference is the pragmatism of the Narcissist: what or whoever seems useful to him deserves a right of existence in his eyes. Each of his decisions is subject to a strict cost-benefit calculation. Of course, this also applies to those decisions that affect his interpersonal relationships. After all, is it a wonder that in his concept even human beings are only resources to satisfy his needs and interests.