Darth Tyrannosaurus

post-rule of 2 the sith tend to keep their "faces" separate, dooku is a strange case. His title of count is actually proper, his family are nobility on the planet he's from, and since he's an ex-jedi, a high profile ex-jedi associated with the grandmaster of the order, his outward face is the one that people associate with his interactions with the seperatists. Since his interacts with the seperatists involve the usage of a red blade and dark side force abilities he's fairly safely "out" as a sith, but WHICH sith he is isn't publically known.