The King, also known as the Monstrosity, is a large and rare form of the Xenomorph XX121 species, that are only known to exist in the largest of Xenomorph hives.[1] They are very similar to the Queen caste but are much more built for combat than the egg-laying Queen.

While known as a counterpart of the Queen, the exact role of the King is unknown. As Ovomorphs do not need to be fertilized, it is unlikely to be a reproductive caste. Most evidence would seem to point to the King being a commander caste like a Praetorian that would act as a hulking field commander for the lesser castes. It is unknown how a King is created and why they only exist in the largest Xenomorph hives.


Among the largest and most terrifying castes that an Alien hive can bring to bear upon its enemies is a creature dubbed the Monstrosity or 'King' Xenomorph. Much like his Queen counterpart, the King possesses an impressive and large head crest, which is much more ornate than the Queen's. The King is also much more rigid, muscular, and heavy than the Queen. Kings are presumably highly intelligent like the Queens.

The King can spit a huge ball of acid which if it hits even a target that is dug in, will melt them to little more than a puddle of matter. When it gets up close, it will unleash a war cry screech before killing its initial enemies and then rushing in with surprising speed for a creature of its size. Its gigantic claws and long tail are able to tear tanks and infantry to pieces in equal measure. Its tail possesses rows of spines similar to the scutes of a crocodile instead of the single row of most Xenomorphs. The King also possesses two barb-tipped tail-like structures on either side of its four dorsal spines.

Ranging in height from slightly taller than a Queen to towering several stories over its smaller brethren, the latter of which shakes the ground wherever it goes, causing small localized earthquakes in its wake. Near impervious to small arms fire, wounds are regenerated almost instantly. It has been noted that when it eats its victims, its alien healing power actually speeds up, knitting even the most terrible wounds back together.[1][2]

Behind the Scenes

Sideshow Collectibles maquette


The Sideshow Collectibles Alien King

Working in direct partnership with Legacy Effects, the artists and nightmare makers behind the creatures and Queen from Aliens, Sideshow Collectibles created the King Alien Marquette to celebrate the 30th anniversary of the Alien franchise.

Standing as a complement to his Queen, the Alien King is a fully-realized canon character. Standing a massive 20" tall and 21" long, the Alien King Maquette strikes a pose of unrelenting drive and energy, accentuated by the seven detailed Alien Drones that swarm around his clawed feet. The King was designed to be much more masculine than the feminine design of the Queen.[2]

Kenner figure


The Kenner Products King Alien.

A 'King' Xenomorph first physically appeared in Kenner Products' 1992 Series 4 of its Aliens toyline. This version of the creature stood more upright and instead of a crest, featured a pair of large mandible-like appendages that when resting, formed the shape of a crest on the head. It was predominantly green in color with black limbs and lower torso (although there was also a completely black reissue).

Other physical distinctions include tusks very similar to those of the Sideshow Collectibles maquette, large blade-like hips and a bulbous sack for a tail which stored acid that it could spit in streams out of its mouth.

Other Kings

The idea of a "King" Xenomorph first appeared in the 1990 unproduced script for Alien3 by Vincent Ward. While being completely different in its design and nature, it is said to be able to spit acid much like the Sideshow Collectibles and Kenner Kings. This version of the King could also implant Chestbursters directly into victims and was able to camouflage itself similar to a chameleon.

The 1993 comic book Aliens: Rogue featured a genetically engineered human/Xenomorph hybrid called the Rogue that was also known as a King Alien.


  • The description for the Sideshow maquette states that this caste of Xenomorph is supposedly canon.
  • The Prodos Games figurine for the Alien King is drastically larger than the earlier Sideshow Collectibles maquette model, being of a similar size to a Queen Mother whereas the maquette stands roughly the same size as a regular Queen and this is most apparent by using the Drones featured in each model as a size reference. It is possible that the difference in size could just be referencing earlier and later developmental stages and this is plausible due to the unparalleled combat advantage that a Xenomorph the size of a Queen Mother would provide without it having to remain immobile to perform the functions that a Queen Mother does and the description given for the Prodos Games model does describe a creature that would be as large as a Queen Mother.
  • The Alien King features tusks similar to those of a Palatine, Raven or a Tusked Xenomorph, though they do not extend past its jaw like those of a Palatine or Tusked Xenomorphs and so are more similar to those of a Raven.



  1. 1.0 1.1 "Alien King - Prodos Games Model".
  2. 2.0 2.1 "Alien King - Maquette by Sideshow Collectibles".
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