From the introduction: Welcome to the world of Kid Icarus: Uprising! You appear a year before the start of canon. Soon the world will be thrown into turmoil as the forces of the underworld rise up and try to conquer the human realm. A plucky young angel and his allies will be all that stands between them and total domination. Even worse is that they are just one of many different enemies that will be making their appearance over the next few years as Nature itself will come looking to wipe out humans, which will attract a fleet of hungry aliens from the conflict who wish to consume all.