The Xeno Menace
Xenomorphs, occasionally known as simply Aliens, are extraterrestrial lifeforms that use other living beings as a host during their life cycle. With black carapaces and wicked sharp claws, powerful night vision, and the ability to see people through walls, xenomorphs are extremely dangerous. They are intelligent and capable of speaking to one another via hivemind, as well as using co-operative tactics, and pose a massive threat to stations if left unchecked.
Xenomorphs most commonly enter a round via random event, with a larva spawning on-station and a random ghost player being given the role; wizardly shenanigans may also result in crew members becoming xenos, and on very rare occasions an egg might find its way into certain Xenobiology setups. As a midround antagonist, xenomorphs can appear during most other types of rounds rather than having their own game mode, and have no explicit objectives other than working together to build a nest, grow in numbers, and eventually force the crew to call the shuttle like cowards take over the station.
The Xenomorph Life Cycle
The lowliest form of Xenomorph is the humble facehugger, the only type of xenomorph not usually player-controlled. Facehuggers hatch from eggs laid by Queens, and on their own simply meander around. If they come close to appropriate prey, typically humans or monkeys, they will launch themselves at their targets, ripping off most (but not all) forms of face protection and aggressively violating their victim's esophagus. The facehugger dies afterwards, but their target will have an alien larva planted inside them, which will fatally burst out of their chest after some time. Note that facehuggers act as pseudo-items, and can be picked up by mature xenomorphs to throw at prey.
Also known as chestbursters, Larva are violently born from the bodies of those who fall prey to facehuggers. When a larva is born, a random ghost player takes control of it, joining the xenomorphs and adding to their growing army. Larva are relatively helpless, having no real offensive capability; instead, they must stay alive long enough to grow into an adult xenomorph. They can crawl through vents to escape danger, and hide under tables to avoid detection. Once they've grown enough, they can become one of three types of xeno: hunters, sentinels, and drones.
The offensive backbone of the xenos, Hunters move at blistering speed and can tackle down their unlucky opponents for quick stuns. Hunters are typically tasked with securing new prey by ventcrawling through the station, facehuggers in hand, looking for lone crew members to throw them at. They're also the best class for starting new outposts and spreading plasma weeds, due to their speed.
Defensive guards of the nest, Sentinels are slower and beefier than Hunters, and can become partially invisible by staying still. Their abilities recharge quicker than Hunters', and they usually stay near nests, keeping any captured humans from escaping and protecting the Drones.
An important type of xenomorph, second only to the Queen, Drones are the builders of the xenomorphs. They can construct resin walls to block pathways, resin nests to keep prey secured, and other such structures. Drones are also the only adult xenomorph capable of further evolution, into a Praetorian.
Praetorians share many of the same abilities as Queens, without the ability to lay eggs. If none exist on the station, Praetorians can evolve into Queens themselves. Each xenomorph colony only has one Queen, and each is a massive engine of destruction, though their real power is in the ability to lay eggs. A nest with no Queen is crippled, and a colony with no Queens, Praetorians or Drones is effectively neutered. Both Praetorians and Queens are also incredibly slow, and the only aliens who can't ventcrawl.
Contrary to popular believe, the Lusty Xenomorph Maid is not actually a valid form of Xenomorph. Stop asking them to lay eggs for you.
Playing As The Xenomorphs
So, you finally got your chance to spawn as a xenomorph? Take a look at the picture: this could be you and your xeno bros, as long as you know what you're doing.
Nine times out of ten, you'll enter the round as a Larva. Larvae are weak as shit, and have the singular goal of surviving long enough to become a productive member of xeno society. All xenomorphs can communicate on the hivemind channel with :a, so try to communicate with anybody else present. If you're lucky, you'll have spawned in a nest, with at least one or two other adult xenomorphs present to protect you and plenty of plasma weeds to roll around in.
If you aren't, you'll be alone, with nobody around to help. Get the fuck to safety! You can hide under tables and crawl through vents (by alt+clicking). As with all xenomorphs, you're also spaceproof, so chilling on the solars is a good plan. Once you've survived long enough, you can evolve into your chosen caste.
No matter which xeno type you become, plasma is your first priority. All adult xenomorphs build up plasma over time, and can spend it to plant weeds. Weeds spread resin around them, and standing on resin boosts your plasma production. Start planting weeds ASAP, and make sure that xeno territory is nice and purple to speed up your recharging time.
Many adult xenomorphs also have access to Corrosive Acid and/or Neurotoxin Spit. Spewing Corrosive Acid onto a structure or object will cause it to slowly melt away, depending on how tough it is. Use it to destroy even the toughest walls, break into secure areas, and generally remodel the station to be more xeno-friendly. Neurotoxin Spit is a ranged stun; to use it, click the ability to ready your gland, then click your target to fire. Both of these abilities use plasma, so make sure you have weeds handy to recharge.
Additionally, all adult xenomorphs have night vision, can see humans through walls, and can loudly rip open airlocks to access prey.
Episode 1: The Xenos Awaken
If you're the only xenomorph alive, for the love of god become a Drone. Being the first xeno means it's your responsibility to bring more xenomorphs to life, and that means you need to evolve into a Queen as soon as possible; spend a bit of plasma to lay down weeds and resin, then sit your ass down and meditate until you unlock your chakra and also get enough plasma to evolve. If you're the only Larva and you evolve into a Hunter, deadchat will dunk on you mercilessly. Also remember that becoming a Praetorian or Queen removes your ability to ventcrawl, so find somewhere safe before growing up.
Being the Queen can be intimidating at first, but the most important thing to do is stay calm and start building a nest. Stay out of sight of the humans, and start plotting where you want to grow your army; ideally, you want somewhere out of the way, defensible, and most importantly with plenty of room to lay eggs. Make sure to hack apart any cameras if you're in a place the AI can see, and consider breaking a window or two to let all the atmosphere out so humans need to bring spacesuits if they want to come knocking.
Once your weeds are down and the floor is creep-y, start devoting all of your plasma energy to shitting out eggs, and hope that nobody comes to toolbox you to death before the facehuggers have hatched. Click fully grown eggs to open them up, click them again to clear them away when the facehugger is out, and plant more. Never stop egging.
When you have a nice pile of eggs and facehuggers, it's time to hunt. If you managed to avoid detection, your best bet is to grab a facehugger in each hand and start moving towards a location with monkeys; Virology and Genetics are two possibilities, depending on what map you're playing on. Monkeys won't fight back, so you can spacewalk to them, break in through a window, throw your huggers, then drag the apes back to the nest.
Of course, you can also go for humans; if you manage to hit one with a thrown hugger, there's a good chance they'll instantly be downed and penetrated. Competent medical staff can surgically remove larva from people if they're fast enough, so drag them to the nest if you can, but prioritize staying alive above all else, because if you die with no successors, it's game over, man.
Remember that Queens are quite robust, and use your tail swing ability to knock away attackers in an emergency; it's extremely powerful, but has a notable cooldown. Most humans without proper gear will lose a melee fight to a Queen, but the real threat comes from ranged attackers; you're fat and slow as hell, and throwing facehuggers is really your only option at range. If a cyborg is on your giant alien ass, or a human gets in melee range, attack them with 
Простой правый клик. Не имеет значения включен или выключен Боевой режим 
Включается при помощи клавиши 4, выключается при помощи клавиши 1 или может быть переключен при помощи клавиши F при стандартной раскладке. Нажатие левой кнопки на людей пустой рукой с включённым боевым режимом приведёт к удару 
или приведёт к помощи 
если он отключен. Также позволяет вам не меняться местами с человеком или толкнуть вас если вы столкнулись.. to stun, then rip them apart.
If you manage to get a single new larva on your side, they're at least a little competent, and you aren't under immediate siege by the humans, you can breathe a sigh of relief. Just having one Hunter to do the reproducing while you chill at home and egg it up is a load off your shoulders, and you can pretty much retire to a life of pumping out babies and hoping you don't get shot to death by the Warden.
The Hunter And The Hunted
If you aren't the first xenomorph, you actually get to pick which caste you want to be. A Hunter is a good choice for the second xenomorph of any given nest, as they're the best at, well, hunting. For starters, you're fast as hell as a Hunter, and ventcrawling lets you get to all sorts of places. Remember to bring a facehugger in each hand whenever you leave the nest to try and throw at humans!
The signature move of the Hunter is the ability to pounce. With your pounce readied, click on a target, and you'll fly at them from a distance, heavily stunning them if you make contact. Beware of humans with shields, or you'll be the one stunned when you ram into them. Once they're stunned, slap a facehugger on your target and drag them away from safety, attacking them on Простой правый клик. Не имеет значения включен или выключен Боевой режим Включается при помощи клавиши 4, выключается при помощи клавиши 1 или может быть переключен при помощи клавиши F при стандартной раскладке. Нажатие левой кнопки на людей пустой рукой с включённым боевым режимом приведёт к удару или приведёт к помощи если он отключен. Также позволяет вам не меняться местами с человеком или толкнуть вас если вы столкнулись.. to keep them down. Don't be afraid to drop them if you need to retreat, and remember that you can rip open airlocks and quickly destroy many machines and structures to sabotage the crew and make a getaway. Don't forget to plant weeds as well, as you can quickly make xeno-friendly pit stops for your fellow aliens across the station.
Hunters can also spit neurotoxin from a distance, giving them a semi-reliable way to stun humans when pouncing is too risky. Compared to other xenomorphs, their plasma reserves are smaller, so make your shots count! Finally, remember to strip your prey of their items, especially their radios.
The Xeno Shitcurity
Sentinels are often the rarest type of xeno; Hunters are the best for aggressive hunting and killing, and Drones are the ones who get to build. If you choose to become a Sentinel, your primary goal is to protect the nest and keep an eye on any still-living prisoners the Hunters drag in. If any of them start to wriggle free of their bindings, shove them back down until their Larva finish exploding out of their chest cavities.
Although you don't have the speed of a Hunter, you can hold much more plasma, and recharge much faster than they do. This makes it much more practical to abuse your Neurotoxin Spit on intruders. You can also use Corrosive Acid more often, so help your Drone friends get rid of any inconvenient walls.
Sentinels have the unique ability to become partially invisible; simply toggle the ability on and fade from view. For best results, stand on resin floors, so you blend in almost perfectly. Stand guard near the entrance, out of sight, and chomp down on anybody who dares enter.
Erectin' A Membrane
If there's already a Queen, being a Drone means you get to actually do Drone things. Drones have the ability to shape several useful structures to build and flesh out a hive.
Resin Walls act as normal walls, letting you build mazes or barricade entryways into the nest. Resin Membranes are tough alien windows; being able to see outside can be useful, but remember that the humans can see in as well. Resin Nests act like beds, and any live humans the Hunters bring to the nest should be 'buckled' to them while their Larva gestate. You should also smash lights, break cameras, depressurize rooms, and generally make the nest as hostile to humans as you can.
Just because you're a Drone doesn't mean you can't fight, although you should ideally be letting the Hunters and Sentinels do it. If the nest is under assault and nobody else is around, it's up to you to protect dat fukken Queen.
If the Queen dies, a Drone is going to have to put on their big girl pants and start evolving, though there's a hefty period after a Queen's death before any more can be created. If you're the only Drone, or even the only survivor, it's going to be you; thankfully, being a Queen is much less stressful if you already have a safe nest. If not, run to safety, drop some weeds, evolve up, and start laying eggs, bucko.
Fighting The Purple Tide
You're a human/moth/lizard/catgirl/etc, minding your own business on Space Station 13, when suddenly you see a penis-headed fuckmonster float by your window, followed by the AI screaming about xeno scum and the Captain shitting himself and calling the shuttle. What do?
The first thing you should do: weld the goddamn vents! Take a welding tool, ideally slap on some eye protection, and get welding to every scrubber and vent in your workplace. Xenos can't pop out of welded vents, meaning doing so cuts off their ability to show up behind you and slap you with a face full of alien wing-wong. Not having any fresh air is usually a worthy price to pay, since established xeno nests are almost always a near-round ending threat.
If you can, find some sort of protective headgear, or hand it to people running off to fight the xenos. Facehuggers can rip off most masks, but bio hoods, riot helmets, hardsuit helmets, space helmets, flipped-down welding masks and more can protect your delicate, tender orifices. If somebody stupid enough to come unprepared gets a facehugger to the face next to you, you might be able to stop the infection by removing it from them fast enough.
Xenos have a notable weakness to fire, meaning if you can manage to avoid burning yourself and your crewmates to death, flamethrowers can be effective. Otherwise, use energy weapons, followed by traditional guns; in a class A emergency, plasmaflooding and incinerating xeno nests might be worth the collateral, but at least warn your allies before doing so. Welding tools are technically effective weapons, but unless you're robust as shit, getting into a melee tangle with a xeno is probably a bad idea. If you're an atmospherics technician, consider bringing plasma through your delivery method of choice and burn the xenomorphs while wearing your fire-proof atmospheric technician's hardsuit. Remember that Larva are weaklings, and beat up any you manage to catch alone.
If you or a friend ends up infected, you have a small window of opportunity to try and preserve them. Alien embryos can be surgically removed if you have Medbay access and you're fast enough to do the procedure; if you're going for it, weld the surgery room's vents and be ready to beat the shit out of the Larva if it pops out prematurely. Remember that even if the host dies, the Larva will still burst out, and hurling an infested body into space is only delaying the xeno's inevitable return.
Xenomorphs love to abuse the fact that they're spaceproof and you aren't, but if you can get your hands on a spacesuit and a jetpack, flying around and attacking from space with guns can be effective. Make them regret busting open those windows!
Because they don't have human rights, Engineering cyborgs dragging welder fuel tanks into xeno nests and blowing them up with their welding tools is a classic anti-xeno tactic, and if things are going to hell anyway, Toxins can toss in a few bombs. Geneticists who can give their most robust allies spaceproofing and hulk genes can be game changers, and Cargo really should be ordering guns in situations like these. If you somehow have the time or foresight to have them ready, Roboticists can build combat mechs.
If all else fails, have a scrappy young crew member walk up to the xeno nest in a RIPLEY; the Queen is obligated under Space Law to engage in a 1v1 duel for the fate of the station.
Xeno Man, Xeno Man, Does Whatever Xenos Can
If you manage to kill a xenomorph, you can surgically extract their internal organs. Alien organs sell for big bucks when shipped off by Cargo, but more importantly, they can be implanted into humans to grant xeno abilities!
Because the only thing better than a clown is a clown with an ovipositor, capable of laying facehugger eggs.
