Protagonist

Protagonist; The protagonist is the primary force in a story or scenario which the audience follows. These terms can not be defined as "Bad Guy" or "Good Guy", as it could work either way depending on who fills what role. For example, in a Mario game, Mario and Luigi are usually the protagonists, while Bowser is the antagonist. However, if you played the game as Bowser, even though he'd be the Villain still, he would also now be the protagonist, while Mario and Luigi, still heroes, would now be the antagonists.

The same could be said about many other groups or characters.