Complex sentence: In the post-apocalyptic world of the "Steelheart" series, random people have gained superpowers, and the new superheroes' (called "Epics") immoral actions have caused the collapse of traditional governments.
Split into simpler sentences: In the post-apocalyptic world of the "Steelheart" series, random people have gained superpowers. These actions of these new super powered individuals, known as "Epics" have caused the collapse of traditional governments.