I'm currently playing around with the notion that all literary genres as we now know them could be extrapolated as coming from three major parent-genres that have theoretically existed since mankind first started telling stories.
This is on balance a heuristic assumption as none of us can know that much about the ways in which early humans developed his first version of what we now call "art/literature." But though the assumption's unproveable, it's not necessarily false.
The three parent-genres would then be:
THE TALE OF HORROR, where the star is the "Monster" who wins out by killing or otherwise defeating the human protagonist
THE TALE OF ADVENTURE, where the star is the Hero, who is presented as being capable of killing the monster even if he goes down the grave with the beastie (Beowulf).
THE TALE OF COMEDY, where the star is the Fool, who has none of the hero's fortitude but somehow, usually via dumb luck provided by the storyteller, manages to survive and win over monstrous threats with much the same outcome as the hero, except for the dying-in-battle thing.
An argument for these forms' history from antiquity to the present is not doable at this time, nor do I plan any time soon to address why I view some of the genres we now know (the "romance," the "drama") as being somewhat less antique. But here's the thought that struck me recently:
As long as the monster of the horror-tale remains just that-- the thing that either "gets you" or at least comes so close that you still feel "got"-- there's not much similarity to the other two parent-genres.
However, when modern serial stories are built around the figure of the monster as a quasi-hero, the writer has to resort to an awful lot of Incredible Good Luck to keep the monster from slaughtering all the sympathetic characters in sight, and keep him somehow focused only on victimizing muggers and rapists (a popular trope of comics and film in the 1970s).
This Incredible Good Luck actually has the effect of making the Serial Monster less of a hero and more like the Serial Fool, whose favorable destiny is carefully rigged by the author.
The Serial Hero also may have Incredible Good Luck at times, but in theory the author is supposed to set things up so that it at least LOOKS like the hero has won through grit and determination, and not by any deus ex machina of his creator.
More on this line of thought later.