9. Dark Danny (Danny Phantom)
Dark Danny - who is also simply known as Dan Phantom - is the evil, full-ghost, future adult version of Danny Phantom, who was created by the fusion of the ghost-halves of the show's titular hero and the his dangerous arch-nemesis, Vlad Plasmius. Dark Danny's first and only appearance in the TV show is in the episode "The Ultimate Enemy", though he was also the villain in the first Danny Phantom video game for the Game Boy Advance. Danny defeated Dan and travelled back in time, knowing that his future wasn't set in stone and that he didn't have to turn in to this evil future version of himself. Voiced by Eric Roberts, Dan is considered one of most dangerous and powerful enemies Danny has ever faced.