So I've seen this idea being flung around a bit, especially with the King's royal debut as a beautifully sculpted Maquette by Sideshow Collectibles, as well as his appearance in the Prodos Game. In all honesty, I really do like the Alien/Xenomorph Queen, or even the Xenomorphs as a whole having a 'masculine' counterpart; But I have also noticed most everyone else doesn't really, for a variety of reasons. Each of which I"ll try to tackle below and offer my own take on them, as well as how a King could function (perhaps in different ways or forms)
1. It's sexist to have a King, especially one that's bigger and stronger than the Queen and the people who made it have no respect for that!
(a) This is perhaps the reason I find amongst the dumbest-for one, the Aliens are technically hermaphroditic (according to Scott and Giger) so the Queen is no more female than 'her' daughters. Not to mention the Aliens themselves, while having very feminine traits, are often described as hyper-masculine due to the fact that they impregnate and rape everything in sight-granted women are capable of rape, but combining this with a Phallic design and the behavior of a sexual predator (which is often male) makes the Alien's third gender much like what I had described-hypermasculine. Disregarding that, how is having a male royal caste sexist? Are ants sexist because most Male Alates/Drone ants are bigger than the average female worker or even soldier? Even still, the King may be big and strong, but the Queen is far more dangerous and important (is the brain behind the Hive, produces Ovomorphs) and if the two did come to blows, the battle would likely end in the Queen's favor like in Aliens Rogue.
(b) The creators behind the Alien King Maquette actually have a fair bit of respect for the concept behind James Cameron's Aliens, which is detailed
here-https://www.youtube.com/watch?v=TSiWpgAaSfk-The various artists and staff working on the project go into detail about how they really wanted it to look like something that would belong in the Alien Universe. Admittedly the line of that there 'should' be a King can come across as kinda obtuse, but I don't think it's meant to be insulting or detracting towards the Queen herself, whom they also spend time praising as both inspiration and as a base point for the King's design (imitation is the sincerest form of flattery)
2. Eusocial Insects don't have Kings, and Aliens are based off of them. So there shouldn't be a King
This one holds a bit more water, as most Eusocial Insects do not in fact have a 'King' amongst them. They do, however, have a 'Royal' Male caste, and one species of Eusocial Insect does have a true 'King'-Termites, of which the Queen's ovipositor is heavily based off of. In addition, there are numerous examples of altruistic, competitive/lek mating, or even ergatoid (combative worker like) males in Ants, Wasps, and Bees. And Army Ants are known for their males being as large as the Queen and in possession of a spiked abdomen and saber like mandibles, as well as having males that are summoned by the Queen during mating periods but otherwise fend for themselves for long stretches of time. So while they're not the mainstay of reproduction or function much like the 'sperm missile' males of Eusocial Insects, they are most certainly not exceptions or even as rare as one would think.
3. The Queen reproduces asexually, so a King isn't needed to mate
This one is fair-Xenomorphs, as far as I know do not sexually reproduce (possible-Female War contradicts this slightly but it's EU and even then...yeesh. Let's save that for Gigerotica, ok?) despite having rather...peculiar tastes (looking at you Big Chap) and rather sensual designs. Granted, 'mating' may not be the right word for it-perhaps helping to build or develop the ovipositor rather than knock her up? And even then, there's nothing to say the 'Male Xenomorph' would actually be mating with the Queen. The title mostly goes so far as refer to a massive Xenomorph with control over others that isn't female/feminine in design, to say nothing that people would assume that if it lays eggs it's gotta be female compared to the male that doesn't, right?
4. What would a King or Male Xenomorph even do? What would be its purpose? Or where would it even come from?
For this section, I've been trying to come up with some reasonable ideas for what an Alien King could do or how it would function, as well as where it could come from. With any luck, something ever so slightly tolerable can come from this-or everyone will hate everything about this, I'unno.
Concept A-The Warlord*: The Alien King is a naturally occurring caste, albeit rare as all hell. It develops during times of plenty where such an extra large caste can be developed without much net loss, and then basically acts as a sort of guardian over the hive. It melds into the Queen's chambers, basically acting as a watchful guardian that sits patiently until it is called upon by the Queen-at which point it tears itself free from the wall it had blended into and roars into action, spurning its daughters and brethren into action not out of the same respect their mother bring, but out of fear. He lacks the exact same level of intelligence, stealth and importance the Queen packs, but he acts as an agile and powerful front line monster to defend the Hive, rally Xenomorph support and, if worst comes to worst, sacrifice himself so the Queen can slip away and start a new hive.
Concept B-The Chimera: This Alien King still occurs in cases where The Hive is large, but instead of occurring naturally its more of a genetic mutation or 'accident', much like the rarish occurrence of Gynandromorphs in Ants (female and male alate hybrids) and/or Diploid males. Basically a batch of eggs goes bad, oozing out with the infamous Black Goo as the Facehugger's embryos meld together into this squealing 'Rat King' of a Xenomorph, eventually growing up into the multiple tailed maquette we see or something similar. The multiple embryonic brains all muddled together to form one big intelligence follows instincts and a territorial cunning, and as such would come to the summons of the Queen much like how a 'free-living' drone ant does. But upon being sighted at the gates, the hive's defenders attack the King and try to slaughter it, who either brushes off the attacks or crushes the opposition as it single-mindedly follows the summons of the Queen. If it survives the onslaught and makes it into the Royal Chambers, the Queen promptly 'tests' it herself, deciding if it deserves to live or not. If it fights her off, she smears it with her Pheromones and keeps the aberration as a pet of sorts...if it doesn't, well, at least they won't have to worry about dinner for a long time.
Concept C-The Disperser: The final concept has the Alien King look more like Vincent Ward's draft on the creature (no barb on the tail, biomechanics and a skin design VERY reminiscent of Necronomicon IV, sharper fangs, etc. See here:
https://i.pinimg.com/originals/3d/5d/a2/3d5da22c46be924ad2191faedd5a2720.jpg,
https://i.pinimg.com/originals/1e/46/c4/1e46c4cc1e361a5f6c2b9e492fbcb1bd.jpg)
The creature is much like the Runner/The Dragon from Alien 3-Fast and vicious in that it is born as a protector of the unborn Queen. It kills or webs up any and all threats, before dragging the Queen Embryo to the nest and either expiring or, perhaps 'fusing' with the Queen when it grows up to supply her with a lifetime supply of male gametes or become the massive fleshy ovipositor she uses to lay eggs with, like an Anglerfish. This kind of King isn't a mass of muscle and armor like the his other incarnations, but he can camouflage his skin in order to blend into the environment, can spew acid, and basically acts as a hyper carnivorous and intelligent facehugger. Perhaps it can even have a sort of proboscis in place of an inner jaw (those fangs probably get the job done well enough) to implant a second embryo in case the first is destroyed, or to simply help web up victims extra fast.
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So, this has been basically a very, VERY long winded rant/suggestion on how to implement and use a 'King Alien' in the massive Aliens Universe. Do I think it's a perfect idea? Dear god no, but after the likes of Chet the Predalien, Resurrection, and the prequels (each of which may have had good ideas and concepts but terrible execution) I figure I can hopefully come up with something objectively better, if only to exist in some distant corner of the Expanded Universe. And if for whatever reason you just utterly despise the concept all together and think I'm a complete idiot, or have some thoughts, please share below.
Thank you for reading.
(*This idea was created by one of my very close friends, and I'm putting this here as a way to credit them)