What if, in the third one...
(if there is a third one)... they have the Xenomorphs and Predators destroy each others' planets, and the colonies that run away go to earth and pretty much fight each other in a competition for the planet's resources with humans stuck in the middle? It'd be even cooler if they got Schwarzenegger, Glover, Weaver, and all those others together as a team to fight off the threat!
Eh.
Just a thought. It'd be neat, is all I'm saying.
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