User blog comment:ChaosWarrior17/Destroy All Monsters 2.0!/@comment-24974663-20140523054826/@comment-24974663-20140523062127

I could see them use Ghidorah as a Earth monster, similar to GMK. But Gigan? It's a cybernetic monster. I can't see it in without treading into man made or Alien creation territory. Anything else would completely throw out it's character, and wouldn't be in line with Edward's authentic Godzilla.

Personally, I would like them to have the Alien monsters introduced as hostile invaders hell-bent to take over the Earth. I could see that work in a third or fourth film.

I think the first sequel should set up the existence of Earth's own monsters.