Emperor Palpatine

He is true main antangonist of Star Wars Episode's IV V and VI he never revealed himself untill V he wanted to first destory Luke Skywalker but instead wanted to turn him like his father but when Luke refused he said So Be It Jedi If you will not be turned you will be destroyed your feeble skills are no match for the power of the dark side only now at the end do you understand now young Skywalker you will die.But Darth Vader redeems himself and chucks Palpatine down the death star main reactor.