A threat from outer space inching its way towards Earth would probably feel too similar to Thanos, who even has a gigantic ship and herald-esque minions.
If they do do a second long-term build-up to a major threat, I'd guess it's going to be mystical in nature, just to maximize difference.
If they do do a second long-term build-up to a major threat, I'd guess it's going to be mystical in nature, just to maximize difference.