well mainly that out of the 3 predators, two of them are killed easily, i mean watching them fight that one alien was like watching a 2 old child fight a lion. however the one "main" predator who is the biggest wuss ever to come from the predator home world because he has a soft spot for humans, well human, kills dozens with relative ease also, in aliens the acid burns through a lot of METAL floors, however this woman's face has developed the ability to with stand this potent acid? i therefore deduce that the woman is in fact a terminator, sent back in time for a completely irrelevant mission....at least my explanation makes more sense then the movie!