Count Dooku was a menacing Sith Lord and central figure in the Clone Wars. Once a Jedi -- trained by Yoda -- he became disillusioned with the Jedi Order and thirsted for greater power. Dooku voluntarily left the light side behind and became Darth Sidious’ dark side disciple, taking the secret name Darth Tyranus and leading the Separatist army. Dooku advanced Sidious’s secret plot to take over the galaxy, but forgot that betrayal is the nature of the Sith.
Scheming, powerful, and evil to the core, Darth Sidious restored the Sith and destroyed the Jedi Order. Living a double life, Sidious was in fact Palpatine, a Naboo Senator and phantom menace. He slowly manipulated the political system of the Galactic Republic until he was named Supreme Chancellor -- and eventually Emperor -- ruling the galaxy through fear and tyranny.
Clone Commander Gree, designation 1004, led the Elite Corps of clone troopers during the Clone Wars. He saw deployments on such heated battlefronts as Kashyyyk. Gree himself wore camouflaged armor to better blend into jungle surroundings. Though a faithful commander who carried out the Jedi's orders, Gree was ultimately loyal to the Republic. When Chancellor Palpatine enacted Order 66, Gree understood it was a worst-case scenario contingency -- the Jedi had betrayed the Republic, and were therefore dangerous enemies of the state.