The Xenomorph (also known as a Xenomorph XX121 or Internecivus raptus, and simply the creature[a])[1][2][3][4] is a fictional endoparasitoid extraterrestrial species that serves as the title antagonist of the Alien and Alien vs. Predator franchises. The species made its debut in the film Alien (1979) and reappeared in the sequels Aliens (1986), Alien 3 (1992), and Alien Resurrection (1997). The species returns in the prequel series, first with a predecessor in Prometheus (2012) and a further evolved form in Alien: Covenant (2017).[5] It also featured in the crossover films Alien vs. Predator (2004) and Aliens vs. Predator: Requiem (2007), with the skull and tail of one of the creatures respectively appearing briefly in Predator 2 (1990) and The Predator (2018), as a protagonist (named 6) in the video game Aliens vs. Predator (2010), and will return in the upcoming FX television series Alien (TBA). In addition, the Xenomorph appears in various literature and video game spin-offs from the franchises. The Xenomorphs' 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. The practical effects for the Xenomorph's head were designed and constructed by Italian special effects designer Carlo Rambaldi. Species design and life cycle have been extensively augmented, sometimes inconsistently, throughout each film.