Xenomorph Queen

In every hive, the Queen is the largest and most intelligent female. She is usually the mother of every Drone and Warrior in the hive, since she is the only one to lay eggs.

Physiology
Queens are much larger than Drones and Warriors. They stand approximately fifteen to twenty feet tall at the hip. They have twin sets of arms and are built more similarly to a large theropod dinosaur than a humanoid. They also have a much larger braincase than the average adult Xenomorph, protected by a large crest above their heads. They also have a slightly stronger tail, which can be used as a weapon, along with their limbs and inner jaw, as shown in the climactic battle with Ripley in Aliens. Due to their immense size, they are extremely strong.

Another well-known feature is the immense ovipositor in the Queen's lower torso, which is responsible for creating eggs (similar to a queen termite). She is able to detach from the ovipositor in an emergency, and will regenerate a new one when the danger is over. Queens also have a higher ability to relate cause and effect, and to make observations and deductions, allowing them a rudimentary understanding of technology in the same way as some primates - ex. The Queen's use of an elevator on LV-426.

The Queen is also considered to be the strongest caste of Xenomorph, able to evenly fight Ripley in a Power Loader in Aliens. Queens seem more resilient to damage than the rest of the hive (even when adjusted for size), as demonstrated in Alien vs. Predator. She receives several deep throat wounds and is speared through the head, and yet remains alive.

Role
Every Queen regulates the entire hive, and it is possible that the hive cannot survive without her. They can fight outside the Xenomorph hive. They are usually nestled deep within the hive, protected by Warrior guards, like an ant queen, who never leaves the nursery chamber of an ant colony.

At the end of Aliens, Ripley threatens to burn an egg when Xenomorph Drones cut off her escape route. The Queen perceives this and beckons the Drones to move out of the way. It is possible that Xenomorph Queens value and protects their species like any good mother would. Nothing short of her own destruction will stop her from seeking vengeance upon those who harm her offspring. In one of the comic book series (released by Dark Horse Comics), a caged Queen becomes hell-bent on killing a human soldier who kills an attacking Xenomorph Warrior.

Design
The Queen's design was created by Aliens director James Cameron (based upon a painting he had done at the start of the project), in collaboration with special effects artist Stan Winston.

The Winston Studio created a test foam-core Queen, before constructing the full hydraulic puppet which was used for most of the scenes. Two people worked the twin sets of arms from inside, and off-screen puppeteers worked her jaws and head. Although the Queen was presented full-body when fighting the power loader at the end of the film, the audience never saw her legs, save those of the small-scale puppet that appear only briefly. It was only during the climax of the 2004 film Alien vs. Predator that audiences could see the Queen running and fighting, because of the computer-generated imagery (CGI) techniques employed to create it.

Alien vs. Predator increased her size to twenty feet. She became more "streamlined", her chest thinner (as there was no longer any need for puppeteers), the "high-heel" protrusions on her legs removed, her joints altered so she could run faster, and her legs made proportionally larger to her body - giving her a sturdier appearance.

Cameron used very selective camera-angles of the Queen - the "less is more" style of photography. Subsequently, the movie won an Oscar for Visual Effect.