Complex sentence: North America is a wasteland ruled by the Daemonites, and most of the Marvel universe superheroes have either been killed or imprisoned, along with several Wildstorm superheroes.
Split into simpler sentences: North America is a wasteland ruled by the Daemonites. By the time of the story's beginning, most of the Marvel Universe superheroes have either been killed or imprisoned, along with several Wildstorm superheroes.