I think that this Ark vessel is a huge Predator transporter that contain a various animals and creatures from space, propably creatures captured by the Bad Blood Predators for their hunt, I think about this like about Lockdown ship from Transformers: Age of Extinction. . it's the same idea, and actually I like it. If the Bad Blood Predators really catch and capture some species, they need for sure some sort of "mobile prison" for that. I guess this Ark vessel fall somewhere on Earth, and after that. . all the creatures escape and some of them perhaps attack both human and Predator characters. I really like this idea, let's wait and see If I have the right. Ohh and btw, I remember these skulls from end of Predator 2, It would be cool if they manage to recreate some or the creatures in this new movie by the looks of these specific skulls.