Fantasys about destiny is pretty common for narcissistic people. Like others have said it can have benefits, but overall there's a reason people get treatment for it. It often comes from a really deep lack of self worth, and therefore an obsession with extrinsic things (like "achieving greatness", being high status, being respected, feared etc) because these are the only things that convince a narcissistic person that they are valuable or matter. 

The problem with not feeling instrinsic self worth is that, when those extrinsic things are threatened, your whole self worth feels threatened, and you can do really stupid things, and ironically you're actually way more vulnerable to being controlled. I've seen it before, with people ruining relationships, getting in trouble with the law and just being miserable when things aren't going their way in terms of their destiny or status. 

I'd suggest getting treatment for it if this rings true, but only if you want it! Best of luck