Grievous

General Grievous also known as Qymaen jai Sheelal when he was a Kaleesh warlord, was the leader of the battle droid army during the Clone Wars. Though, they are various depictions of General Grievous throughout Star Wars:

Different Grievouses

 * General Grievous (Canon) (the recent crazy version of Grievous, this is one most people hate)
 * 2003 General Grievous (the first General Grievous, introduced as a villain in the cartoon)
 * 2005 General Grievous (the first General Grievous, to most Star Wars fans, introduced as a villain in the movie
 * 2008 General Grievous (introduced as a hero in cartoon)