I wasn't thinking about that possibility, but that's interesting. To elaborate on my ideas I'll connect them to the lyrics:
Back at base, bugs in the software
Flash the message, "Some thing's out there"
Floating in the summer sky. - Continuing with the "balloons" thing, weather balloons are generally conncted to alien visitation conspiracies as a way of disproving that we... I mean they exist. "something's out there." Some speculation on this: X-files, aliens in general or potentially the franchise or something to do with conspiracies, maybe even dead space or interstellar terror. "Panic lads, it's a red alert. There's something here from somewhere else"
"The war machine springs to life
Opens up one eager eye
Focusing it on the sky."
"With orders to identify, to clarify and classify
Scrambling in the summer sky."
Simplifying even further: "Back at base, bugs in the software" could have something to do with shadowcreek labs, havoc: dogs of war.
Also, a militaristic post apocalypse might be a possibility.
Also, given the song was in German, it could potentially be a toungue in cheek reference to nazis taking over or something. That's probably some people guessed Nazi zombies.
Moving away from the song however, I had these ideas: 100 year anniversary.
Sweet 16 was another party themed hhn, could we see a return of classic icons in much the same way as that year?
The movie IT. Or potentially the book.
Balloons could be a red herring as well. What's the opposite of a reason to celebrate? Death? Undeath?
Treaks and Foons
Cindy
Other than that, that's all I've got.
About terra cruentas though: I could find nothing of burning, however this: http://halloweenhorrornights.wikia.com/wiki/Terra_Cruentas says that the cycle of terra cruentas was broken when the Queen sacrificed herself. Unless burning is a metaphor for them losing everything, I don't think that terra cruentas has any relation to this. I could be wrong however. I didn't attend that event.