If you're inventing evil characters who require badass names, save yourself some trouble and first consult the TV Tropes Wiki, where there's a long section titled Names to Run Away from Really Fast. A few examples:
Anything that ends in the letter R (since villains have to do things in order to be villains): Himmler, Hitler, Lecter, Vader, etc.
Anything with Mor, since mort is Latin for death: Mordred, Mordor, Moriarty, Voldemort, etc.
The colors red and black and their synonyms (Blackguard, Blackbeard, Dr. Raven Sable, Red Sonja).
Ancient dead languages: "If someone has a name that's Latin, or Mesopotamian, or Babylonian; this probably means they were around back then. A rule of thumb is usually the older something magical is, the more powerful. Expect Ominous Latin Chanting."
Xtreme Kool Letterz: Axel (exception: Axel Foley of Beverly Hills Cop), Draxo, Vilgax, Thrax, and Zero, "which is a name with a page unto itself."
Then there's the very illuminating list of "famous murderers and assassins," where we get this:
Any variant of the name Cain qualifies. (You have the first Cain who murdered his brother, Cain from Trinity Blood, Kain the titular vampire from Blood Omen: Legacy of Kain, Kain from Final Fantasy IV, Kane the WWEwrestler, John Lithgow's character from Raising Cain, Admiral Cain on Battlestar Galactica, and so on etc...
And you were wondering when I was going to get around to politics.
(I've written previously about the endlessly fascinating and useful TV Tropes Wiki; read the post.)