This chapter's epigraph is from the opening lines of the novel. It's a quote from the novel's first chapter, "In which the hero of the story is a genius who has come up with a way to defeat the enemy." In other words, the hero is a smart person who has figured out a way of defeating the enemy. This is the first time that the hero has been able to defeat an enemy, and he's done it in such a way that no one else can do it. He's also the first hero to defeat a single demon beast, which means that he has killed more than a hundred thousand demon beasts in the process. Now that the demon beasts have reached the third defense line, they're ready to attack the city walls.