What does this mean? Zombies, of course! Some abandoned secondary locations will be invaded by zombie hordes, and traveling between locations might result in a zombie ambush. Not only that, during the invasion, you'll also get access to the special Plague Event side quest. We'll have you shouting "Braaains!" in no time.
Also, make sure to check out zombies' names when you encounter them--you never know who may have come back as the living dead. :)
