The empire-wide criminal syndycate. Regularly destroyed, yet ancient and everlasting.
Secretive, elusive, ruthless... and terrible to the point where even some eldritch abominations want to have nothing to do with it.
A group of mages that decided that magic has to go - or at least be taken under control.
1/5 human supremacism, 1/5 transhumanism, 3/5 evil.
Egalitarians, all the way into utopian insanity.