The Space Jockey Xenomorph is giant and rare Alien type that is born from an Engineer, also known as a Space Jockey. This article covers all the individual Space Jockey Aliens featured in Alien lore, including the Deacon from Prometheus and the Titan Xenomorph from Aliens: Dark Descent. These creatures have portrayed with big differences, even hinting at the possibility that Engineers and Space Jockeys are not the same race.
The Original Space Jockey Xenomorph
The most well-known Space Jockey Xenomorph is the one that emerged from the LV-426 Space Jockey on the Derelict ship from the first Alien movie. Unfortunately, we never got to see it, although judging from the hole in the chest, it was almost the size of a human upon birth. Behind-the-scenes material for the movie revealed a deleted concept of an unknown fossil near the Derelict that the Nostromo crew don't notice. Perhaps this was the Xenomorph that exited the ship and died. Another fate for this Space Jockey Alien is revealed in the Alien: River Of Pain book, where Newt's parents enter the Derelict and see another dead Space Jockey locked in an embrace with an Alien Queen.
The Apocalypse Space Jockey Xenomorph
The Space Jockey Xenomorph's appearance was revealed in the epic Aliens: Apocalypse comic book, which bore many similarities with the Prometheus movie released much later. In the comic, an ancient Space Jockey is awakened for stasis and impregnated by a facehugger. This Space Jockey did not look like the Engineers we saw later - it was a giant grey-skinned elephant man with long hair. The resulting Xenomorph (nicknamed The Destroyer) was unsurprisingly huge but did not have any special particularities, despite the size. It acted aggressively against everyone, including much smaller fellow Xenomorphs.
Prometheus took the Space Jockeys in another direction, revealed to be blue-skinned humanoids in Jockey suits that were somewhat smaller than their elephant-man counterparts. The creature the Engineer gave birth to was different as well - it was not a Xenomorph, but a "Deacon". The Deacon was the result of a complex and unpredictable life cycle, caused initially by the Black Goo Pathogen, a bioweapon developed by the Engineers. The Deacon had blue skin, a sharp tip at the back of the head, and a pink inner mouth. Following the events of Prometheus, the creature was stuck on the planet after everyone died or left. In the Fire and Stone comic series, it was absurdly revealed that the Deacon grew into an organic mountain around the Prometheus ship wreckage.
The Engineer Mural Xenomorph
Before the birth of the Deacon, a Xenomorph mural on the ceiling of the Engineer bioweapons facility foreshadowed a potential "Engineer Xenomorph". Perhaps this was a creature that the Engineers were striving to create or created long ago and now kept as a reminder. Some Engineers might have even worshipped this strange mural, bowing down to a "perfect creature". As shown at the beginning of Prometheus, the Engineers sometimes sacrificed themselves to create new life, so maybe this "Mural Xenomorph" was intended to be born from an Engineer as well. Later on, David created a strain of Xenomorphs (the Protomorphs) using the Engineer's plans.
In the script for Ridley Scott's "Prometheus," writer Jon Spaihts introduced the Ultramorph, a terrifying evolution of the Xenomorph, emerging as a chestburster from an Engineer, described as dark gray, armored, and hideously large at birth, rapidly growing to human size. This lethal creature, which bled green acid blood, was to hunt the character Jocelyn Watts, showcasing brutal resilience in a fierce confrontation. Artist Carlos Huante later refined its design, inspired by H.R. Giger's Necronom IV, adding a biomechanical appearance and elements like a Beluga whale-shaped forehead. The Ultramorph represented a prehistoric variant of the Xenomorph, potentially growing to immense sizes and exploring themes of genetic influence and biomechanical evolution, an idea originally suggested by Ridley Scott for the original alien's design.
The Space Jockey Xenomorph With A Trunk
The Aliens: Infestation Nintendo DS game introduced yet another representation of the Space Jockey Xenomorph, a giant brownish creature with an organic trunk. This was supposed to be the result of the Xenomorphs DNA reflex - taking traits from the host, namely the elephant-like Space Jockeys, not the Engineers seen later in Prometheus. The creature attacked the Colonial Marine player on the same LV-426 Derelict that appeared in the movies and was most likely the "original" Xenomorph. The Space Jockey Alien could spit acid, but was not the toughest boss fight in the game - a much larger Alien Queen appeared later in the game.
The Titan Xenomorph
Finally, we have the giant Titan Xenomorph from the excellent Alien: Dark Descent video game. Intriguingly, the game introduces a third representation of the "Space Jockey" race, called "Ancients Citizens", but these might not be Space Jockeys at all. Regardless, a huge creature is born from one of the "Ancients", and acts as a final boss for the Colonial Marine squad in the game. The Titan Xenomorph had big and strong arms, but its legs were tiny, somewhat hindering its movement. It lacked a lower jaw but had a trunk-like inner jaw, somewhat similar to the Aliens Infestation Xenomorph. A very long tail gave it a snake-like appearance.
In conclusion, the Space Jockey Xenomorph is one of the biggest Xenomorph types, but it lacks a definite appearance, and its characteristics seem to change each time. This is somewhat tied to the lore of the Space Jockeys being changed in the Prometheus movies. We might have not seen the last of the Space Jockey Alien, as its recent appearance in Aliens: Dark Descent proves. However, with Prometheus 3 and Alien 5 canceled, the upcoming Alien: Romulus movie and the FX Alien TV series have promised to stay away from the "Prometheus" lore for the time being.