First off, I think it depends on which variation of each character is fighting. Which alien? Face hugger, soldier, queen? What year of Jason? Freddy is the same, just a repeat of the same bag of tricks on different kids and we all know what sort of things the Predators carry. If it's a queen, I'll put my money on her, facehugger... how's he going to get past predator mask and jasons mask or get Freddy at all, soldier, might be able to take out one, but not all of them. Jason from the first movie, and Alien would most likely dismember him before he could cut through the exoskeleton. Jason from the year 3000 or something movie, he could probably take out an alien and maybe even the predator.
In my final note, just cause no one has said it... Pyramid Head would own them all. Thank you.
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