Only I Can Do That!

Narcissists hate it when one of their royal subjects says "Me too!" or or "I have had a similar experience" or "I can relate, I've been through that", or "I enjoy/don't enjoy that also" or "I am into that as well".

They only like it if someone they have put on a pedestal says those things.

They also hate it when someone does something well, or something that other people might pay attention to. Unless the Narcissist can somehow take credit for what the other person does, they would rather that person disappear.

(If you can remember elementary school, there was often a kid who would say things like "You can't be the pitcher! Only Mike can be the pitcher!" or "You can't draw as good as Stacy, only she draws good!" or "You can't be the team captain, only I get to be captain!")

The reason is because they create status hierarchies with other people; this one is "below" me, that one is "below" me, that one is "above" me. No one is equal to them, and can only be higher or lower than them in their minds. And therefore everyone else must abide by their hierarchy creation as well, or they are "wrong".
If they deem something as a "higher minded" thing, then anyone who is "lower" than them CAN'T know it or relate to it. For example, if they deem fine woodworking as a "higher minded" thing, than YOU CAN'T KNOW how to do it, because you are "lower". So if you SAY "I love fine woodworking, I have been doing it for a long time" they will become annoyed, even angry, even accuse you of making it up to "get attention". You could show them the furniture set you finished last week, and even if they make noises to your face like "ahh" or "Oh I see you really do practice fine woodworking" they will STILL diminish it, and promptly mentally delete the evidence that proves their assumption wrong. When the subject comes up again, they will act just the way they did before about it, as if there is NO REASON to believe you have ANY IDEA how to do fine woodworking.
Most emotionally healthy people LIKE it when they find common ground with another person, or when someone they know does something they admire. Narcissists DO NOT, because it makes them feel less special, less unique, less elite, less ABOVE. They don't want you singing on the stage with them, they don't want you to have the same talent as they do, they don't want you to already know something that they pride themselves on knowing, they don't want you to be able to do something that they do, they don't even want you to love the same play, movie, band, or hobby with the same intensity that they do. They don't want you to be able to do something that one of their HEROES does, especially.
THEIR passions are ALWAYS more intense than yours, their knowledge is always more extensive than yours, their family and friendship bonds are always deeper than yours, they are more worthy of LOVE and RESPECT than you are. You can NEVER be an "equal" in anything, unless they have decided that it would serve them. Once they have deemed you as "lower", that is where you will stay in their eyes, always.
(Taking them seriously with their hierarchy creations is something a lot of people fall for, until they realize what's going on.)
The narcissist's social hierarchy creations have NOTHING to do with real status and hierarchies, which are essential in certain groups such as families, businesses, and public service, for communication, learning, and functionality. These hierarchies are real, and have nothing to do with who is "liked" or "worthy" and who is not. In a real (and healthy) hierarchy, positions exist for actual reasons, not because of popularity. (Obviously Narcs infiltrate these groups and inject their own influence, corrupting the real functionality, but the reasons those hierarchies exist are legitimate and not about intrinsic personal "worthiness")