A Queen is a huge Xenomorph that serves as the mother and leader of a xenomorph hive. Her appearance differs from that of a drone, with a pair of extra arms and a large head crest. She is the largest, strongest and the second most intelligent Xenomorph of the species, after the Queen Mother.
They can engage in combat, but usually remain stationary, letting the Praetorians (or drones and warriors, if none have developed yet), do their dirty work while they direct the hive and lay the eggs. A Queen can disconnect from its egg sack by pulling its tail out as seen in the 2010 AVP video game. A Queen is much more intelligent than a normal Xenomorph, displaying traits of anger and vengeance beyond any purely instinctual behavior. An example of this is when the Queen saw her nest destroyed by Ellen Ripley, but more importantly, Ripley killed all her children and then began a murderous rampage in an attempt to kill both Ripley and Newt, even going so far as to hide herself in the landing gear of their dropship and follow them back to the USS Sulaco. Ultimately, Ripley finished the Queen off by throwing her out the air lock.
A Queen was held in suspended animation by Predator technology on Earth in an immense pyramid under Bouvet Island. When three youngblood Predators came for their manhood ritual hunt, which activated the pyramid, the Queen was thawed from cryo stasis. She immediately started laying eggs and was eventually freed by her "hive". She was presumably killed when Alexa and Scar managed to wrap her chain around a water tower which they then dropped into the Southern Ocean below where she presumably died.
Another queen was seen in Aliens. This Queen is the chief antagonist of Aliens. The Queen is the mother and leader of the Xenomorph hive on LV-426. The Queen lived in a large chamber with hundreds of eggs and several guards. It was killed by Ripley when it was blasted out of the airlock of the Sulaco and into the vacuum of space.
In Aliens: Steel Egg a Queen chestburster emerged from one of the crew of the ship. It was one of only three facehuggers, the rest were destroyed in their eggs. There was no mention of a difference in appearance from other facehuggers. With that being said it could be that out of any batch of eggs they all have the potential to be Queens but only if one isn't already present. While the nurse was performing the procedure to try and remove the embryo, the host, not of his own control but of something else's will, tried to keep her from cutting him open. The Queen was obviously trying to protect itself from death and an early birth. Regardless of the operation it emerged from the incision, quickly attacking and killing the nurse and partially devouring her and then also killed and devoured its host which had tried to flee with the gaping hole in his chest because of the drugs, local anestesia and the fact that the embryo was cut out it didn't burst out.
Biology
A queen fighting Ellen Ripley.
A royal facehugger is the preferred method of developing a queen. It is a facehugger with a darker coloration who can implant a normal embryo and a royal embryo into a host. A variant of this appeared in the Aliens vs. Predator comic and appeared to be slightly darker in coloration than a normal facehugger, and had what appeared to be bristles or spines on its back. It ,apparently, only contained a Royal embryo.
Before becoming a Queen, the royal chestburster develops into a Praetorian, which can then transform into various other specialized forms at least in Alien vs Predator: Extinction.
It is possible for a typical drone/female warrior Alien to develop into a queen in the absence of either a Royal facehugger or a Praetorian Facehugger, as long as it lives long enough to undergo transformation into a Praetorian. In a deleted scene from Alien, the alien appeared to have been turning some of its prey into eggs, perhaps showing the early stages of such a transformation, or perhaps it was trying to create a Royal facehugger that would be able to create a queen. In AVP: Requiem, the Predalien, born from a normal facehugger and capable of impregnating hosts (preferably pregnant women) directly, rather than laying eggs. It is possible that this was simply to establish a hive. More likely is the possibility that this form of "breeding" is a trait inherited from its Predator host, and may be unique to that species.
The Matriarch closeup.
Combat
The Queen, despite her size ratio compared to other Aliens, can sustain near-limitless gunfire before having to retreat. Due to this, once outside of her larvae facility, the Queen can destroy most prey within seconds. It has also been noted that the Queen displays numerous signs of extreme muscle density, making hand-to-hand fighting a lesser-used tactic in AVP. Her height will often vary greatly, at times being roughly 15 feet and sometimes can grow to as large as 40 feet.
Intelligence.
The Queen is the second most intelligent breed of Xenomorph and they have been shown to know how to operate machines and somewhat understand humans (actions, not speech) as the Aliens Queen "told" her warriors to back off when Ripley threatened her eggs. It should be said though that all Aliens have shown intelligence in some respects, namely observation learning but it is known that the queen is superior. In the film Aliens and the comic Aliens vs Predator: Deadliest of the Species, the Queen has shown to communicate and "bargain" with humans, in Aliens, the Queen had her warriors back off after Ripley threatens her eggs with a flamethrower, though Ripley later kills the eggs anyway after one opens, either due to the belief that the Queen did it or didn't believe a facehugger would be restrained by the queen and would attack them. In Deadliest of the Species, Caryn threatens a royal egg with a spear to get the Queen to release her friends, the Queen, however, begins squeezing them till they bleed, giving Caryn her own threat. Caryn then places the egg in front of the Queen telling her she (Caryn) will be a host to a royal facehugger if she (the Queen) lets her friends go, the Queen complies and releases the captive humans and gives Caryn a royal facehugger, which Caryn uses to facehug herself. The Queen, from that point on, protects the group though this is instinct to protect her heir than actually protecting the group because of a deal.
The Queen appears to be much more intelligent than other Xenomorphs. This is seen in Aliens when she uses a service elevator to get to Ripley, though this could be common sense as she grew up in the facility and most other Xenomorphs would have learned to operate human technology.
In AVP, the Queen appears much larger than the one in Aliens, mostly due to age since the Queen in Aliens only lived for at least a week and the Queen in AVP lived for thousands of years. However, younger queens can still grow to that size.
It is also shown that the Queen can be made from warriors. One example being Specimen 6 and possibly the Predalien (Chet).
The attack on Ripley and the marines in the complex in Aliens could have possibly been ordered by the Queen.
When Ripley threatened the eggs, the Queen ordered her warriors to refrain from attacking Ripley and Newt.
The Queen in AVP3 appears different to the other Queens seen thus far. She had a white coloration and the covering of her mouth was wrinkled and broken in some places. The differences in her appearance may be due to her advanced age or perhaps the fact that the humans stole her Royal Jelly.
