I agree that there is, sadly, nothing past getting set up.
I have a great idea I think: Once the day horde 7 arrives, the day turns to 100 and starts ticking DOWN! The place will be nuked because a new "Blood Moon Zone" has been detected by an automated global defense system!
Built years ago by the surviving governments, its location and current status are unknown.
You have 100 days to live and try to find the location of the control center or find a way to leave the area, past an unknown amount of radiated landscapes and hope to find a place free of the zombie menace! How do you know this? Have you done this before??