Alien vs. Predator (often abbreviated “AvP”) is a science fiction / horror fiction series spanning several forms of media. The series is a crossover between two popular movie streams about extraterrestrial beings: Alien (whose creatures are known as "Xenomorphs") and Predator (whose aliens are known as the "Yautja"). In AvP, the two species are in conflict with one another because of human actions. The idea for such a crossover is often thought to have originated from a Xenomorph skull seen as a Predator's trophy in Predator 2, but Dark Horse Comics published their first Alien vs.