Darth Sidious

A Sith lord, Darth Sidious was the prime practitioner of "The Dark Side of the Force". In Star Wars Episode I: The Phantom Menace, Sidious sent out his apprentice Darth Maul to kill Queen Padme Amidala and the Jedi knights Qui-Gon Jinn and Obi-Wan Kenobi.

In Star Wars Episode II: Attack of the Clones, Sidious again plotted against the Jedi, this time sending his new apprentice Count Dooku, a.k.a Darth Tyranus to do his work.

Darth Sidious was eventually killed by the Jedi in the final battle between the Jedi and the Sith.