they need us before they can wipe us out

Not sure if its been mentioned before as iv not read all the new posts but from the trailer its obvious the alien gods/SJ's left evidence of a invitation because they need a human host to carry on their race, or if they want to release the weapon on earth they also need a human seed to do that, otherwise they could of done it anytime.. sounded better in my head lol. It hurts my head hearing all the theory's about who's morphing into who or if the alien on the wall is a happy meal toy. we've been shown all we guna see untill the movie comes out but it still don't give too much away