Xenomorphs
The Alien is a fictional endoparasitoid extraterrestrial species that serves as the titular antagonist of the Alien film series. The species made its debut in the film Alien and reappeared in the sequels Aliens, Alien 3, and Alien Resurrection. The species returns in the prequel series, first with a predecessor in Prometheus and a further evolved form in Alien: Covenant. It also featured in the crossover films Alien vs. Predator and Aliens vs. Predator: Requiem, with the skull and tail of one of the creatures respectively appearing briefly in Predator 2 and The Predator, and will return in the FX television series Alien. In addition, the Alien appears in various literature and video game spin-offs from the franchises. The Aliens' design is credited to Swiss surrealist and artist H. R. Giger, originating in a lithograph titled Necronom IV and refined for the series's first film, Alien.