Plasma was pretty great, I really like the split they dd in B2W2. Misguided idealists led by power-hungry cunts are where real live problems stem from (See: Nazis, Isis, tumblr)
Plus Ghetsis is the most evil Poke-bad guy. Abducting and grooming a child, leading a bunch of well-meaning people into criminality, the whole creepy religious aspect Plasma had to it. The absolute bomb though was straight up trying to kill Nate/Rosa. No villain in any Pokemon game has gone that far.
