Call them the sociopaths who want to rule the world. It's accurate enough. They don't rule yet (and never will if enough of us have anything to say about it), though they control enough to make life hard for everyone, and they are most certainly driven by greed and self interest with a complete lack of empathy for any living thing.

We could refer to them all collectively as Leeroy Jenkins. I believe Leeroy/Leroy means "the king", though in this context it lacks the connotations which you mention.

TPTB (The Powers That Be) aptly fits.

It's all-encompassing and covers any individual or group that collectively hold authority over a particular domain.