There are very few true heroes because there is practically no such thing as good vs. evil, only point of view vs. point of view, so, one who is a hero from one point of view is probably a villain from the other. The only true heroes are those who act selflessly and for the betterment of all man kind. There are also situations like WWII where Ally soildiers might've liberated thousands from a deathcamp by killing only hundreds of Nazis, at times like that heroism is derived from statistics.