That was largely why I never got into the reversed roles RPing - my character genuinely believes himself a hero, and a case can very easily be made that he is not a villain per se.
Xorn isn't a villain in the truest sense of the word either. He's a misguided hero, a champion of justice. Love is the root of all misery, he believes, and thus it must be rooted out.
The thing is that a protagonist pushes the story forward/drives the story, whereas the antagonist obstructs the protagonist in reaching a conclusion. I don't know where Woundwort's from, but if the main character of the show has a wish and Woundwort's wish is opposed to that, he is a right proper antagonist─just not necessarily a villain.
Zero is not an antagonist at all, as Lelouch's Rebellion is about, you guessed it, Lelouch and his rebellion. The entire series follows Lelouch as he pushes his vision onto the world and tries to mold it into the shape he desires. At some point Suzaku is an antagonist, until he does a face heel turn and becomes a supporting character. The black knights start out as supporting characters, but later become an antagonistic group. His brother is always an antagonist, as is his father. As far as antagonists go, Lelouch doesn't fit because he is demonstrably the protagonist of the story; It's his story, and his wishes that move the story forward. This is not open to as much interpretation as people would have you believe, but generally those people think "antagonist" = "bad guy".
conq and i and probably some other people knew what antagonist means and we're murrcan so i don't see why you're bringing nationality into this??
Because I Can. <( ̄︶ ̄)> I had a big discussion elsewhere about protagonists and antagonists, and they were all Americans and honestly believed "antagonist" equalled "bad guy", and "protagonist" equalled "good guy". They went on to say not every story has a protagonist. This is patently bullshit, because without a protagonist you have no story.