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======Xenomorph======
EXTRATERRESTRIAL STAFF
Alien.png
Alien	Alt. Titles: None
Access: Any unwelded vent, or door you can melt down.
Difficulty: HARD
Supervisors: The Queen
Duties: Protect the queen, build the nest, multiply.
Guides: No external guides
A lot of people like aliens, either playing as, fighting against, or being faceraped caressed by them. Alien events don't occur very often, but reading this guide will prepare you in the event that it happens.

Remember, as an alien you can use :a to talk to the hivemind.

Contents
1 Overview
1.1 As a Xeno
1.1.1 Prologue - Facehuggers
1.1.2 Phase One - As a Larva
1.1.3 Phase Two - As an Adult Xeno
1.1.3.1 Hunter:
1.1.3.2 Sentinel:
1.1.3.3 Drone:
1.1.3.4 Now comes decision time. Do you want to evolve into a queen or be a marauding hunter/sentinel?
1.1.4 Phase Three - As a Queen
1.1.5 General Advice
2 As a Human
2.1 XENOS!
2.2 AI why is comms down? AI?
2.3 Shit man this is just like that one movie...
2.4 CHOOSE YOUR DEPARTMENT
2.5 Xeno counters
3 Fluff
3.1 Facehugger
3.2 Larva
3.3 Adult
3.4 Queen
4 Oddities
5 Supplementary Video
Overview
Aliens arrive on the station in one of three ways.

The first way is for the random event where CentCom broadcasts that an Unidentified Lifesign has been detected aboard the station. This means that in a very few random places around the station, a handful of alien larvae have been spawned. They can pop up almost anywhere, even right next to you.

The second way is for admins to spawn them. This can either be as a forced random event that is exactly like the CentCom alert, or by just spawning some alien larvae.

The third way is for a miner to find a facehugger on the mining asteroid, get facehugged/get somebody else facehugged, and bring the resulting larva to the station.

As a Xeno
Alien-Infested Escape Shuttle
This guide is fairly comprehensive and long. Playing as aliens and against aliens takes some finesse, so make sure to read it all.

Prologue - Facehuggers
An alien is on my face, help!

If a facehugger jumps onto, or is thrown onto someones face, it usually rips off the mask (if they have one) and attempts to infect the person it's on. If the facehugger is taken off in the first few seconds, the person is usually not affected. Some helmets/masks will prevent facehuggers from latching onto your face, such as Bio Hoods.

Being facehugged is not a guarantee of infestation. There is at least a small chance that you will not become the host to an alien Larva.

If you've been infected, there will usually be telltale signs. You'll feel sick. Your throat will be sore. You'll cough a lot. Near the end, you'll feel something trying to tear its way out of your chest. These symptoms mean you are forming a larva. Using a Health Analyzer will show an Unidentified Foreign Body if you are infected.

There are a couple of way to deal with this. Either ripping out the larva through Surgery, or having you scanned and ready to clone when you eventually explode. Note that you will be gibbed when the larva comes out, so there's very little hope for you after that.

You may just be killed to stop the infection from spreading if none of these options are available to you.

Phase One - As a Larva
I'm a larva, what do I do?

You've just spawned and are weak as shit.
Above the chat window is your status window. It has index tabs. Click the Alien tab. It shows you all your alien powers.
As a larva you cannot attack and you have no special alien powers aside from 'Crawl through Vent' and 'Hide'.
You can talk to the hivemind by using 'say ":a' (e.g. Say ":a Hey mom, what should I evolve into?").

If there's anyone around when you burst, you may be spotted and killed. Run for your life. Finding a vent is your best, and probably only chance of survival.

If you're not in a good spot, find the nearest vent and crawl through it.
A good spot is anywhere where you A) are not likely to be found and B) have an easy access vent. If it's dark, that's even better, since someone who comes inside may not see you unless they get close.
You can crawl through vents faster than anyone is going to react to your presence, so don't be afraid to scout out as many locations as you can to figure out the best place to hide.

If for any reason your hiding place is found out, don't be afraid to crawl through the vents and find a new place.
If you're stuck in a room with no vents, and doors you can't open, turn "hide" on in the alien tab and hide under the table. Hopefully nobody will know you're there.
Once you're in your spot, sit and wait to evolve.
You evolve faster if you sit in weeds.
Under your 'Status' tab, there's a progress bar. When it reaches 200, you'll recieve a pop-up window with choices on how to evolve.

Phase Two - As an Adult Xeno
I'm a Xeno! Now what?

As an adult Xeno, you have a lot more freedom in what you can do. Your intents are slightly different from a humans.

Help - You nuzzle other aliens and caress humans. Fairly pointless cute.
Stun - You tackle humans and knock them down for quite a while. You also harmlessly bite other Xenos.
Harm - You slash at humans doing ~20 damage. You can also 'wound' them which causes them to fall over and deals an extra ~10 damage. You also harmlessly bite other Xenos.
Grab - Much the same as a human, however when you aggressively grab a human, you can then click yourself to devour them. This takes some time, and they can escape if they aren't stunned. Be careful, as humans can still move around in your stomach, and if they have sharp implements, they may just break out. You also harmlessly bite other Xenos.
Hunt and Stalk are Run and Walk respectively.
Below are a summary of the classes:

If you are the first, or one of the first Larva to evolve, you want to become a Drone, as you'll need a Queen to be able to make eggs, then get facehuggers, then make more larva.

STOP RIGHT THERE. Don't just run off to kill people. Or ever. Infesting is always better than killing.
As an alien, killing someone is something you never want to do. Ever. Killing them means you can't get them infested, and infesting them is what you want to be doing.
Revealing yourself now is probably not a good move. Hold off until you've built up your nest.
Xenomorphs run on plasma. Your body stores plasma and your powers need it to work. You can absorb plasma two ways: plasma in the air and weeds. These effects can stack. Below are a list of some of your powers:

Hunter:
Hunters - Are strong and agile, able to hunt away from the hive and rapidly move through ventilation shafts. Hunters generate plasma slowly and have low reserves. The fastest and strongest physically.
Has 150% health.
Builds 5 plasma per tick, to a maximum of 150 plasma.
Hits for around ~22 damage.
Stalkers Camouflage - Hunters have an innate ability to blend into their environment whenever they are toggled from Run (Hunt)/Walk (Stalk). It is much more effective in low-light areas, so make sure to break lights or slash APC's. Drains plasma while active.
Crawl through Vent - Requires no plasma and is exactly the same as doing it as a larva.
Plant Weeds - Takes (50) plasma, and it something you should be doing often. Makes purple sacs which spawn weeds around them and allow aliens to heal and build up plasma on them. Again, these are very important.
Regurgitate - Takes no plasma, and expels anyone you have devoured from your stomach. You can devour people by grabbing them aggressively and then clicking on yourself, though it takes a while.
Transfer Plasma - Allows you to transfer an amount of plasma to another alien, as long as you're adjacent to them.
Whisper - Takes (10) plasma, and allows you to send a private message to anyone in sight range. Can be understood by anyone, even humans.
Sentinel:
Sentinels - Are tasked with protecting the hive. They are not as fast as the hunters, but compensate with abilities that let them attack from longer ranges and are no less deadly in melee.
Has 150% health.
Builds 10 plasma per tick, to a maximum of 250 plasma.
Hits for around ~20 damage.
Corrode with Acid - Takes (200) plasma and can melt almost any object adjacent to you. It does take a while though, and can't melt reinforced walls. Also appears in the right-click menu.
Crawl through Vent - Requires no plasma and is exactly the same as doing it as a larva.
Plant Weeds - Takes (50) plasma, and it something you should be doing often. Makes purple sacs which spawn weeds around them and allow aliens to heal and build up plasma on them. Again, these are very important. You should probably leave this to the Drones, unless you're stuck in some lonely part of the station. If so, plant some weeds so you have some Neurotoxin Darts ready.
Spit Neurotoxin - Takes (50) plasma and causes anyone hit to fall over for a short time. Travels faster than a taser electrode and will usually hit them if they stay in your line of sight. Applies toxin damage in increments.
Transfer Plasma - Allows you to transfer an amount of plasma to another alien, as long as you're adjacent to them.
Whisper - Takes (10) plasma, and allows you to send a private message to anyone in sight range. Can be understood by anyone, even humans.
Drone:
Drones - Are the working class, offering the largest plasma storage and generation. They are the only caste which may evolve again, turning into the dreaded alien queen. The weakest and slowest.
Has 100% health.
Builds 15 plasma per tick, to a maximum of 500 plasma.
Hits for around ~18 damage.
Corrode with Acid - Takes (200) plasma and can melt almost any object adjacent to you. It does take a while though, and can't melt reinforced walls. Also appears in the right-click menu.
Crawl through Vent - Requires no plasma and is exactly the same as doing it as a larva.
Evolve - Takes (500) plasma, and allows a drone to evolve into a Queen.
Plant Weeds - Takes (50) plasma, and it something you should be doing often. Makes purple sacs which spawn weeds around them and allow aliens to heal and build up plasma on them. Again, these are very important. A Drone should almost always be doing this until a room is infested with Vines and Weeds for optimal plasma generation.
Shape Resin - Takes (75) plasma and allows you to spawn a resin wall, nest, or membrane where you're standing. Membranes let light through but are weaker, walls are stronger but don't block light. Nests keep your prey from running off and seeking medical treatment when they've been attacked by facehuggers, and also secrete chemicals that keep them from dying before the new larvae burst out of them.
Transfer Plasma - Allows you to transfer an amount of plasma to another alien, as long as you're adjacent to them.
Whisper - Takes (10) plasma, and allows you to send a private message to anyone in sight range. Can be understood by anyone, even humans.
Now comes decision time. Do you want to evolve into a queen or be a marauding hunter/sentinel?
If you are the first (or one of the first) aliens, you should evolve into a queen. Without a queen, there is no way to spawn additional facehuggers, and no way to expand the brood. Aliens are not a threat without facehuggers, so queens are a must-have.
If there's already a queen, you can choose to stay as a regular adult and start creating chaos. There are good reasons to do this. Queens move slow and cannot vent crawl, so having hunter aliens makes collecting new hosts much easier. Sentinels will be valuable for protecting your nest, and an extra drone can be valuable if the queen dies unexpectedly.
For the sake of this guide we will assume you are one of the first aliens, but if you join as an alien partway into the infestation of the station you can skip to the final phase.

Since you probably want to become a queen, you'll have to pick Drone. Your best bet is to just sit tight and build up 500 plasma to evolve. The sooner, the better.
The crew may probably be looking for you at this point, so make sure you're in a relatively safe spot.
Once you evolve you are very slow and won't be able to vent crawl. You will be very vulnerable until you build up an army of facehuggers, so plan your nesting ground accordingly.
If for any reason you know that the genetics lab or xenobiology lab are no longer being used and the monkeys are still alive, nest there.
During this time you can continue to scout around through various vents and see where people on the station are.
Jumping through vents and planting additional weeds in random places is a great way to divert attention from wherever your actual nest is. The crew will be distracted at the sight of weeds, so it's often worth it even though it does slow your progression to queen.
Now it's time to play the waiting game again. 500 plasma and it's on to phase three.
Phase Three - As a Queen
I'm a queen, but how is babby formed?

Queen - Large, slow, and slightly tougher, but not any more physically powerful than the rest of the Xenos. The only Xeno that can lay facehugger eggs.
Has 250% health.
Builds 20 plasma per tick, to a maximum of 500 plasma.
Hits for around ~18 damage.
Powers:

Corrode with Acid
Lay Egg - Takes (75) plasma. Your unique skill. Lays an egg which will hatch into a facehugger. Facehuggers can then be used to make more larvae.
Plant Weeds
Spit Corrosive Acid
Spit Neurotoxin
Transfer Plasma
Whisper
Let's get this out of the way. First, you can caress anyone with your scythe-like arm by clicking on them an empty hand, with the Help intent active, while they're next to you. This has absolutely no effect.
You're a queen. Awesome. You get some nifty positives and negatives compared to regular aliens. Let's go over them.
Cons: You are slow as fuck. Snail's pace. You also can't vent crawl. You basically have zero mobility compared to everything else in the game. You also stand out with a unique sprite.
Pros: You can lay eggs, you build plasma much faster, and you have more health.
Your first task is to lay an egg. You start with 250 plasma even though you needed 500 to evolve, and you'll build more very quickly.
If at any point in time you have plasma built up and don't know what to do with it, lay another egg. Laying more eggs increases the facehugger swarm and is your best weapon against the humans.
You can open any door that isn't ID locked, but locked and/or bolted doors require that you spit corrosive acid on them. Corrosive acid is your all-access pass to the station. If you're stuck for any reason, or want to get in somewhere (example, rooms with monkeys or plasma tanks), use acid. It takes a while to eat through doors usually, so spit early and lay eggs while you wait.
Alone, aliens are weak, and a queen even more so. One lucky assistant with a toolbox to the head can end your infestation very quickly, so don't let it happen. Always lay low and keep a wall of eggs and facehuggers between you and anywhere humans can get at you from.
Remember to spit Neurotoxin on those who get too close (right-click them, or use your alien tab). This should stun them for long enough to let you get away.
You can take items off humans in order to make it harder for them to escape/kill your brood.
Drag anyone you incapacitate back towards the heart of your hive. Make sure that when they get back up, a facehugger will be within jumping range. Once they're impregnated, feel free to drag them into a nest so they can't escape, then wait until they explode into a new alien baby.
Alternatively, grab 2 or 3 facehuggers and pocket them. Drag the body on the hive while he's stunned from the facehugger.
Monkeys are viable facehugger targets, and are a fantastic way to rapidly expand the size of your brood without needing to hunt down humans. From a meta standpoint, they also let more players into the game without killing anyone, so it gets more ghosts back to playing, which is always good.
Once you've amassed an army of facehuggers, and hopefully ambushed a couple of unsuspecting crew who were unfortunate enough to stumble on your nest, you should communicate closely with the other aliens and prepare to start really branching out across the station. You've already started this, probably, especially since the other alien players are probably being more aggressive than you. The hunters should ambush and devour humans so they can be brought back to the nest, the sentinels should stay by the nest and repel any attackers, and the drones should plant weeds and create resin to slow any intruders.
General Advice
When first starting off, KEEP YOUR HUMANS ALIVE. Don't kill people initially or fuck up the air in your nest.
You do not need air to breathe as a Xenomorph! Feel free to walk around the outside of the station and make a good safe area to plant weeds and store plasma on (i.e., the solars, or toxins test area if no one is bombing or has bombed it). You can also spit acid on windows/grills to destroy them, so any window is a potential entry point.
If you're a drone and/or Queen, being spaced can actually be a good thing. If the threat of an angry crew is on one side and the void of space is on the other, by all means space yourself. You can survive the depths of space, and you will eventually land somewhere and thus be able to remake your nest.
The vents are savehavens. If you hide in there long enough the crew might forget about you.
You can see in the dark, and humans can't. Destroying light sources may be useful.
The moment you or your friends are seen, expect the shuttle to be called within a good five minutes or so. A powerful Alien is a stealthy alien.
You can disable borgs. Any borg that isn't combat is an free kill if you manage to disarm them, as it disables them for a good chuck of time.The stun time is powerful, and disarming a borg into the direction of a door opens it.
Don't slash APCs, they deal damage to you and its better to break lights and cameras (which is safer) and keep some items online, such as disposal chutes (which you can use to throw away borgs or yourself when in a bind) and other machines you can still interact with.
You can hide in lockers.
You can hide facehuggers in lockers.
You can hide yourself and a facehugger in a locker then create a resin door.
Place weeds or nests over eggs. The sprites go over them allowing the eggs to appear a true suprise.
Place nests, a lot of them. Empty nests are where you put the fuckers you infest or are going to infest
Place eggs in clusters, in various spots as you move into the station.
place facehuggers around corners, under items and in tight spots.
Weeds will not grow on things that block their path, be sure to bust down all window pieces and tables/closets in order to expand where the weeds grow.
Its safer to acid electrified grilles, faster to just go around.
If the crew knows there is xenos, it might be best to not nest in viro, as they will all rush there once they hear the word "XENO" on the radio. Good places to nest are Xenobio, Engineering, or the AI core, if there is no AI.
When humans stop coming towards the nest, begin to move towards the humans. If you are in viro be sure to slowly move your way into medbay.
Be sure to use acid on important things like Engineerings SMES, Telecommunications and the Particle Accelerator.
Be aware that, currently, facehuggers have no air giving abilities. You may want to make sure Atmospherics for the room are not compromised otherwise you may lose the chance to infest monkeys or even people.
You can ventcrawl and steal monkeys to bring back to the nest by devouring them and regurgitating them in the nest.
When you infest a player, they will gib into a xeno that IS NOT the same player, which means it selects from a ghost. If you are having trouble gaining larva from your infestees, it may be best to kill the ones who resist the most as they will be reborn again later.
Usually if your infestation goes well, the admins will send in an ERT or worse, a Deathsquad. In such cases its best to ambush ones that get separated and pick them off one by one. Remember to use the vents!
Aliens can alt-click on mobs to spit neurotoxin at them.
Aliens can ctrl-click on other aliens to transfer plasma to them.
Oh how the tables have turned.
As a Human
XENOS!
Keep a cool head maggot. Xenos are either a minor inconvenience or a huge fucking deal.
Get some protection. No not that kind, hardsuit helmets, Bio hoods or even pumpkin helmets can't get fucked by facehuggers. Generally a good thing to have when they are about. Due to recent updates, facehuggers can tear your helmet off too! Be careful not to run into a nest full of eggs without methodically destroying them or having a borg do it.
WELD THEM FUCKIN' VENTS.
If the xenos seem competent (either the first few morons who ran in to kill xenos got raped or somehow the xenos got big without people finding out) it may be a good idea to get a fucking gun. For quick reference, Lasers>Projectile guns>Stunning/High damage melee weapons>Melee weapons.
If someone gets infested, make sure they get medical care ASAP. Surgery can remove a xenomorph Larva, but otherwise cloning will have to do.
If no other option is available, killing Gibbing or isolating the infected will help stop the spread of xenomorphs.
Crew members may seek to make peaceful contact with the aliens. This can lead to peaceful cooperation for both parties, but may just end up in a large amount of dead on both sides.
AI why is comms down? AI?
If all other options have failed, combat may be the only option.

Try to declare red alert. This will at the very least keep people alert, and may get you access to the Emergency Response Team.
Lasers and bullets work on Xenomorphs, however, they also work on people. Keep your firing lanes clear!
Melee weapons are not recommended unless you're in groups. A single Xenomorph can tackle you and then have enough time to put a facehugger on you or kill you.
To avoid increasing Xeno numbers, destroying monkeys may be useful, but its a good way to get called names in OOC and the thread.
Restrain Murder individuals who wish to spread the infection or are helping hostile xenomorphs.
Flashes don't work on xenomorphs, though flashbangs do.
You best bet to escape a fight is to use a stun weapon and then run. Stunning xenos wont paralyze them but it will slow them down.
If fighting to kill (which should not be done unless absolutely necessary) stunning and then beating is effective.
Larva should be killed if possible.
Use riot shields they can block disarm attempts by xenos and neurotoxin blasts. Deathsquad/Nuke op E-sheilds are the same thing, only better.
Welding vents restrict Xenomorph mobility.
Fire works on structures made by Xenomorphs *(alien weeds, eggs, purple sacs, etc.), but Xenos themselves are immune to fire and cold.
Seriously consider calling the escape shuttle.
Some departments have their own ways of dealing with xenos. Roboticists should build mechs, Rnd should print guns, Engineering should weld the vents, Atmos could fill the scrubber pipes with very hot gas in order to kill any that get in there (Don't do that with the main (blue) loop, unless you are a traitor), Botany can produce pumpkin helmets which can protect people, so on and so forth.
Don't be a hero. Be smart. Don't rush into a nest for glory, make plans and go over ideas with other crewmembers.
The Science and Engineering Departments are vital. They both can single handedly end xeno infestations given room and supplies.
As an AI, it might be smarter to contain the humans away from xenos. Humans (players) are stupid enough to get in situations that will only cause more harm. It might be smarter to prevent anyone from feeding the xenos and force everyone to get organized around some plan.
Good plan: Mech busting through and drawing xeno attention while a team comes in from space.
Bad plan: "Ill just run in there with the whole armory and kill all the xenos myself!"
Shit man this is just like that one movie...
So you are the last man left alive and all your friends have disappeared or been dragged off

Make sure you're the only one left. Use radios, intercoms, or PDA messages to contact any potential survivors.
If you have weapons, use them.
Make your way to the bridge or the captain's quarters and try to call the shuttle. It's the only way out now.
If you are eaten alive by xenos, there's only one way out. Take out your oxygen bottle or any other weapon in your hand, and move around as much as possible. You'll slam the thing you're holding into the alien's stomach lining, and if you do it enough you may explode out of the aliens chest cavity like some kind of reverse-larvae. Sharp implements work best.
If the shuttle isn't coming, call it so the rightful xeno race can rule the stars. Or message Centcomm to call an Deathsquad.
Call Centcomm and ask for the nuke code. It might be the universe's last hope.
Beg the queen for your life, it may work. (yeah right)
If the shuttle is here, get on it, weld the doors shut, make sure nothing is in there with you, and hide as best you can. Central Command has a plan for this sort of thing. Fuck that shit, grab a toolbox and syndie balloon and prove how robust you are.
CHOOSE YOUR DEPARTMENT
Different departments have different ways of dealing with xenos, so depending on where you are, you may or may not be screwed.

Engineering
Become Isaac Clarke, only with xenos. Your tools, combined with your fellow engineers assistance, can take down a few xenos that get too close, and your hardsuit helmet will stop facehuggers. Engineering is a prime target for xenos. Electrified grills will do a little bit of damage to xenos, but if the engines are wired to grid, and you have enough power, you could be able to kill them instantly! (Be sure to tell the crew this.) Remember, you control the air, power, and comms, keeping them online will make sure EVERYONE survives. Also, be sure to weld vents and doors!

Security
Probably the best department suited for a xeno infestation. Your hardsuits will protect you against facehuggers, like engineering's. Your main advantage is weaponry. While science may take longer, you have instant access (assuming the AI, HoS, or warden are there) to laser weapons. The brig is pretty well defended, and with it's own medbay, you can order surgery items to stop your fellow redsuits from becoming your next target. Coordination with other departments is also a good idea.

Medbay
Oh boy, this isn't gonna be fun. Medbay is the WORST area during a xeno infestation. With genetics and virology close, xenos would LOVE to set up nests there, especially virology. Get biosuits and medical hardsuits, you're gonna need em sooner or later, you poor soul. However, it's not all that bad, your department is still one of the vital ones, and people are going to need medical aid now more than ever. Be sure to keep weapons on you, as one lone xeno can ruin everything in medbay. Chemists can experiment with different ways to keep people alive while on the move, because chances are that they won't have time for a checkup.

Cargo
CARGONIA STRONK. Your department is VERY important, all those thoughts of becoming independent, making emitter defenses, getting guns, gloves, and pizza are all acceptable. First off, GET GUNS, GET MORE GUNS, AND THEN A FEW MORE GUNS. Make sure everyone in cargo has a weapon, or you're screwed. Your cargo bay should be your main base of operations, so re-enforcing the entrance, welding vents, and adding turrets are all good ideas. As a miner, your hardsuit protects you, just as all the others. In fact, you could even make a base on the asteroid, far away from any xenos. But doing this will sacrifice your precious supply shuttle, so consider your other options. If you're feeling REALLY ballsy, you could collect a bunch of Goliaths, and send them to fight the xenos, but don't expect it to work out well. Also, science still needs resources, so consider giving them some and they may give you a nice advanced energy gun for your troubles!

Science
OH BOY TIME TO MAKE GUNS! If miners gave you resources, start making guns, if not, you're kinda in a pickle here. Robotocists have the ability to make more borgs, and while it's (hopefully) code red, borgs unlock the combat module, which is a xeno's worst nightmare. Robotocist ALSO have surgery equipment, so they can remove alien embryos. Xenoarchs and Xenobiologists should focus on RnD, as finding some right slime or artifact takes too long, and not worth it. Toxins COULD team up with telesci to send a bomb into a xeno nest, but if you're a non-antag, ask an admin first. Remember, if you don't have the resources, you're toothless, so kindly ask beg the miners.

Silicons
You are probably one of the best "departments" for fighting xenos with the combat borg module enabled. You have laser weapons that recharge all the time, and cannot be facehugged. Keep an eye on your power- without it, you're dead in the water, so always keep an eye on how much you have left. More importantly, if a xeno gets close enough to disarm you it will stun you for a VERY long time- more than enough for it to turn you into scrap metal, especially if there's more than one present. Never go into a xeno nest without backup- it only takes one xeno to outmaneuver you and stunlock you to death.

The roboticist should be your best friend, if you are damaged severely, he's probably the only one who gives a shit about you, so make sure he stays alive. Combat is the obvious module you should pick, medical or engineering or mining could also work. AIs have a total view of the station (except for maintenance) so finding a xeno nest should be pretty easy. Electrifying doors will give any xeno a nasty shock, and if you disable safety protocols, you can spam shift+leftclick on a door to make your own tiny xeno smasher. MoMMIs just do yer job and stay away from the queen. (Unless you are going to try and make friends by dancing.)

Civilian / Service
I'll just tell you now, it's unlikely that you're going to survive. Seriously consider teaming up with sec or cargo for guns and a better chance at survival. However, a few jobs are still important. Chefs and botanists should keep the crew fed, as hunger will slow them down, and could cause them to die. Bartender should make doctors delight to keep people on their feet. The chaplain can incinerate or space xenos, if they're knocked down. The rest of you should SERIOUSLY consider helping sec or cargo.

Clown
Become the hero that the station needs, but does not deserve. Godspeed, you absolute fucking madman.

Xeno counters
Sometimes simple outlines can help strategies for both sides, here's pros and cons of different attack techniques against xenos.

Guns and weapons
Pros: Does the job. Shoot xenos enough and they die. RnD weapons are even better for their high DPS, especially the AEG with its ability to recharge itself over time. Most xenos have no ranged attack, and those that do must spend plasma to use it.

Cons: If some asshole hordes the guns and gets captured you now don't have those guns. Additionally Xenos can melt them with their acid, removing the guns forever. Additionally, the RnD weapons have high research requirements and material costs and require armory access to open the lockboxes they come in. (Though shooting them open or using an IED works too.)

Combat borgs
Pros: Has a ranged attack and thermals. Shields and mobility. A good player as a combat mech spells doom to xenos who are slow, such as a lone queen.

Cons: A single disarm can lead to the borg's demise. Additionally, borgs require power, and their modules soak up lots of that. If they're out of power, they're basically shit out of luck. Combat borgs also require Code Red to be in place. If for whatever reason you can't call code red (e.g. no surviving Heads of Staff), you won't be able to build combat borgs or reclassify existing borgs to the combat module.

Mechs
Pros: Bulky, facehugger proof and has kickass offensive and defensive attachments. Also is airtight. Your best bet is a Durand or a Gygax, but a Ripley can work too under the right circumstances.

Cons: Aliens have no attack delay against mechs. More than 3 attacking the mech at once can destroy it quickly if it does not have a melee defense module and/or a repair droid. Running out of power can also be an issue.

Hot gas
Pros: Fucks up xenos quickly if they don't know whats going on reliably. Filling pipe lines with this restricts their movement without having to weld vents, though filling the vent/distro/fill/Blue pipes with hot gas as a non-antag easily can net you a bannu.

Cons: Aliens can flee to space, though that might be a pro since it forces xenos out of their once fortified position, but it also makes entering superheated areas a pain for later.

Electrocuted grilles
Pros: Good area denial.

Cons: Tedious to set up. Requires LOTS of power in the network to grill xenos. Xenos can just use their acid to melt them if they wise up.

Explosives
Pros: Turns xenos inside out.

Cons: Turns everything else on the station inside out too. Will be more destructive than the xenos themselves, and will likely get you banned if you do it when you aren't an antagonist.

Fluff
Facehugger
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A parasitic cycle in xenomorph production with the appearance of two human hands held together and attached to a spiny, powerful tail. It has a proboscis it uses to implant embryos and provide oxygen while strangling a victim. The finger-like appendages are used for transportation and to attach itself firmly to a host body.

Once implantation is complete, the facehugger falls off and dies. Removal of a facehugger while it is copulating is always fatal for the victim, either because of a snapped neck, trauma from the facehugger ripping off the face of its victim, or the powerfully acidic blood of the xeno. Victims rarely remember implantation or even the act of being jumped in most cases, likely because of the asphyxiation caused by a facehugger's tail during the process and the psychological trauma of the act. haha no

Once implanted, the host will have symptoms such as sore throat, coughing, and etc. With a med-hud showing a purple icon near the healthbar. This indicates that a larva is there, so do something about it. Note, that even if facehugged, the host retains a SMALL chance to have no larva implanted, and consider themselves lucky as fuck.

Like all of the xenomorph species, not much is understood about its growth, motivations, or senses, but it is known that a facehugger can tell the difference between a living humanoid and a non-living humanoid such as corpses or cyborgs and that they are suicidally focused on reproduction. Xenomorphs often use crowds of facehuggers to take down large prey or grouped or well-defended humans.

Larva
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Also known as chestbursters because of their method of exodus from the host body, larval xenomorphs are the third known stage in reproduction for that species. While developing in the body, xenomorph embryos attach to blood vessels to absorb nutrients and complete its unstable genetic structure using the host's DNA.

Through an unknown process, this always results in a functioning offspring. This form is small compared to the adult, limbless, and serpentine. They have a strong instinct to hide after forcing their way out through the ribcage and violently tearing their host body apart. If left alone, xenomorph larva will undergo an unknown transformation process to adulthood.

It is believed at this stage that the xenomorph is at its most vulnerable due to its small size and apparent lack of many senses, though this should not be misunderstood -- a larva is still deadly. Its powerful thrashing and sharp teeth got it out of a human sternum, after all.

Adult
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This form is usually the last in any given xenomorph's life cycle. There are many different castes of xenomorphs, but the three most common subtypes are the hunter, the sentinel, and the drone.

The fully grown xenomorph sports a phallic-shaped skull with hidden, mostly useless eyes protected by a one-way transparent dome. It has a host of esoteric senses, most prominently a theorized echolocation (explaining their near-constant hissing) and electroreception, though its primary sense appears to be smell. The scent of pheromones is experimentally shown to be the primary communication device of xenomorphs, most effectively transmitted by the ropey purple weeds the adults spread around the station. It is unknown where this tissue comes from, as xenomorphs refuse to make it in captivity.

The primary byproduct of this weed is the strange substance plasma and as such most corporations are extremely interested in the connection between the xenomorphs and that chemical for production reasons. Like the facehugger, the hunter's blood is highly acidic, and there are rumors that it is capable of eating even through space station hulls, though it must be said that this is only a rumor.

The adult xenomorph is a living weapon, with an exoskeleton thick enough to absorb or redirect most trauma and temperature extremes, scythe-like claws, and a multi-tiered jaw system capable of projecting an acidic compound presumably from their stomachs. Some varieties of xenomorph are crested, and most varieties have a heavy tail with protective ridges. Xenomorphs at this stage show semi-sapience and problem-solving abilities, and are capable of using pack-oriented tactics, creative stealth, and psychological manipulation. It is reported that in the presence of enough plasma xenomorphs can communicate in a basic way with sentient species, but there is little evidence to lend credence to such an absurd notion.

Hunters serve as the xenomorph brood's main way of collecting prey for the brood. Despite their powerful build, they are astoundingly swift and supposedly can make themselves nearly invisible. Whether this is a product of their speed or something more unusual is uncertain. Reports also indicate that they will consume victims as a means of transport, regurgitating them once they are secured.

Sentinels are the brood's primary line of defense against intruders. With a potent mixture of neurotoxins in their saliva and the ability to melt through most walls with a burst of acid, they will attempt to guard the Queen with their lives or die trying. Though they are not as swift as Hunters, they are no less robust.

Drones serve as the menial laborers of a xenomorph brood. Their role entails mass-producing the purple weeds as well as constructing fortifications from a resinous substance they secrete. Despite their apparent weakness by comparison, they are vital to a xenomorph brood's survival, as only a Drone can later metamorphose into a Queen.

Queen
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Very few xenomorphs undergo the transformation into queen. It appears to be done only in the case of very specific hive pressures. They are the only xenomorphs capable of laying the eggs that hatch facehuggers. While much larger than the other adults, they're also much slower, but are indeed much tougher. Even accounting for the size difference, a xenomorph queen can take drastically more punishment. A queen is most likely found where there are high levels of plasma, surrounded by other xenomorphs and swarms of freshly hatched facehuggers.

They are significantly more intelligent and highly protective of their offspring. While slow, they have many of the adaptations and weapons of their other castes, a larger, thicker crest to protect their brain casing, and higher internal stores of plasma which they can utilize for the shaping of resin, the laying of eggs, destructive survival defenses, and the blind dedication of her brood in regards to her safety. Like all xenomorphs, there is little information about them. Rumor has it that an even more dangerous variant of the Queen referred to as an "Empress" exists, but nobody sent to investigate these claims has ever been heard from again.

Oddities
You can perform CPR on any Xeno as a human, but they have to be under -50% HP and have suffocation damage for it to work.
Below 0% HP , aliens will gasp, but not take suffocation damage. Below -50% HP, they'll pass out and take suffocation damage.
Larva cannot die when they reach full progress and recieve a pop-up window.
Regular Aliens can't understand humans, and humans can't understand aliens. A pAI with a universal translator can talk to them, and a Queen is able to converse normally. Regular aliens can whisper into a humans head to talk to them.