Aliens. They are living weapons, the incarnation of sexuality, fear, and savagery given form. A Predator might be a mighty warrior, but they pall against the physical perfection of the Alien.
Okay, fanboyishness aside, the Aliens still win. They have an exo-skeleton that deflects armor-piercing explosive 10mm bullets, a prehensile bladed tail with the strength to whip around the body of a hunter at will, razor-sharp claws, a tongue that punches through pred-metal, and a life-cycle that makes them nearly impossible to eliminate.
