Note: While this Guide is good, be able to counter enemy strategies on the fly and don't be surprised if anything fails hard or succeeds when it simply shouldn't.
The definition of strategy
Strategy, as we are talking about it, doesn't talk about how you build your walls, or gives tactics for everything, through I do list some tactics in here. It is an overview of a battle, and to look at the principles in the war vs the Marines. Don't expect everything to be covered here, but do expect to know a ton.
Pre-Stage 1
Prepare your defenses, get all the monkies/furry hosts, and try to kill the survivors. After Marines arrive try to pick lone marines off. Don't try to impreg though if your far away from the hive, just kill.
Stage 1, or the deadliest stage of them all.
If there is a stage that Marines win overwhelming/definitive victories the most, it is this stage. If you keep reading, understand that Attrition and Time is on your side. The marines are generally stronger than you and will annihilate you if you tried to actually battle against them on their terms. Marines are stronger early game, Attrition is your greatest ally. Marines have set up a effective table fort and is beginning the push on you.
Strategies Section 1: Xenos generally win wars of attrition:
Why do Xenos outclass marines in wars of attrition? Lets look at the mechanics that are important in a attrition war.
Healing
Xenos can heal on weeds by resting for a bit. As long as you don't die even in crit you will get back up after a period of time and you can rest and heal. This works well.
Marines have to expend limited medical supplies to heal minor wounds, and have to be sent back to the ship if they need surgery or are injured badly enough.
Numbers
Early on Xenos are outnumbered about 1 xeno to 4 marines or 1 xeno to 5 marines. It isn't balanced directly by quality, either, a marine can kill a T1 or maybe even a T2 if they are lucky and catch them in the open.
However, often we see those numbers drop to many 1 xeno per 2 marines or less due to facehugging. If this happens, do not assume you've won. Pushing out as Xenos is the turning point of the match, if you push out, get CASed or shot down, you may end up with a few xenos vs 60ish marines and lose, even if you manage to kill tons of marines. We'll talk more about this later.
Growth
Xenos grow into T2s, T3s, and get upgraded just from surviving. Xenos however, are limited in growth to T2s and T3s from the total number of aliens there are, so this can stall if people aren't getting converted. The upgrading mechanic is independent of this, however.
Marines however, don't have much in terms of growth over a round. Yes, CAS may grow stronger with more and better guns over the round, and more Requisition points flow in too, but buying the same crate increases cost. Generally marines won't grow much farther. Not to mention Ammo will make them be weaker over time as they lose resources.
Reinforcements
Xenos dominate in this field. Any marine that is impregnated Is a new Xeno for the hive. This is very valuable, and while one impreg isn't worth your life, this can very much snowball into crazy numbers, which also allows the senior Xenos to evolve into more T2s and T3s. This can snowball into a Marine defeat. Marines denying impregnation is one of the most valuable things they can be doing other than killing Xenos.
Marines do have some reinforcements from late spawns, but generally late spawns missed the briefing and don't really know much. Getting those late spawns into the field is valuable, but it pales in comparison to Xenos. Not to mention Ammo and AP ammo. AP ammo is rare.
Light and Darkness
As Xenos, Darkness is one of your greatest allies. Ambushing marines in darkness is a piece of cake even for drones. Even if you're not ambushing, hiding in darkness will allow you to dodge shots at you and make enemies miss trying to shoot at the darkness. Toggle your darkness sight on and off to fully utilize this, but don't become over-reliant and make sure you can still escape if things go sour/Flamethrowers.
Marines' Flares can be Acided to death, not only to drain on their flares, as that is a resource too, but to also allow the cover of darkness.
Defenses
This is more about Xenos, but also covers marines too. Xenos can delay a flanking force with a hivelord for up to 10 minutes just by spewing tons of walls. The general weakness of hives is just getting shot/CAS/destroyed from range, but creative building of a Hivelord can delay and allow Xenos to get up close. Xenos are superior in defenses, as they only take plasma instead of metal.
Marines' defenses aren't actually all that bad. They are worse than Xenos due to reliance on metal and you can't build that much that big without time due to limited metal, However, time is exactly what Marine engineers have. The front lines generally take a while to be overrun, and mines, turrets, and barricades can really mess up a Xeno push or at least allow more Marines to retreat, denying impregnations.
As you can see Marines generally will lose attrition battles attacking a Xeno defense. Really, the point is that the best thing you can do as a Xeno is not die in a attrition style defense, even if it means ceding land or health. Saving other Xenos from death is also a great thing to do, your numbers are everything. Every xeno that isn't traded for 7 marines dead is a loss while you are defending. The last thing we learn from this is that Marines are stronger early game, and Xenos get stronger later the game goes on and the longer they are delayed with minimal casualties.
Strategies Mini-section 1.5: Defense in Depth.
What is a Defense in Depth? It is where you cede land instead of casualties. This is crucial to winning as Xenos. There are 3 "resources" you have as Xenos and 5 "resources" your Enemy has. Numbers, Space, and Time. Marines also have Information as a valuable resource that they can gain and Supplies as valuable resources they lose. Numbers is the amount of forces or Xenos on your side. Space in this case is the distance away from your hive you're defending. Time is the amount of time it takes for you or the enemy to complete objectives, like pushing, setting up telecomms, and other things. You do not have the numbers on your side as Xenos to afford losses. If you have a choice, cede Space over Numbers. Time and Information are also important. Do your best to deny that too.
Examples at denying time and Information: Make it look like you're retreating to the Hive, but you are retreating in another direction that isn't the Hive. This is just one example. Attacking a lone, split up squad trying to set up telecomms that is too spread out across Telecomms and a Building with a dedicated 10+ alien assault can not only cause causalities, but delay a valuable objective. Time and numbers wasted, even if the number trade isn't as efficient as we'd like it to be, its worth it.
Strategies Section 2: Vs Fire and supporting
This section is for the Builder Caste and Queens and talks about Pheromones. Pheromones are useful as Xenos, specifically, the healing pheromone, the attack pheromone, and the defense pheromone. If you have nothing else to do, just Pheromoning a defensive line with defense pheromones, and switching to warding/recovery pheromones (recovery if the Queen is already doing it.) when a Xeno is in Crit and is on Fire can really help. Attack Pheromones are for dodging bullets and attacking, really. Doing this minimizes Xeno casualties and lets Xenos tank that extra shot they needed to escape, or survive Fire. Fire is very deadly vs Xenos, Why? Xenos can often escape into defenses or cover at low health, but Fire requires either 2 to 3 drops and rolls which lower tiered and low-health xenos need about half of their life to pull off. However, if Xenos are in crit, they can't extinguish themselves. The best thing to do, is to call for the Queen to activate warding pheromones (and you activate recovery pheromones) and to Queen-heal the Xeno on Fire. Edit: Knowing what Pheromones to use when is extremely important.
Edit: Pheromones of the same do not stack, the strongest Pheromone of each is used. If you a drone and there is an already active pheromones of warding already, activate other types of pheromones. It helps.
Resin Defenses
Setting Resin walls to be used as cover, and allowing Xenos to advance under cover protected from gunfire is generally the end goal of defenses. The other end goal of defenses is delaying the enemy and assisting your Xenos to out attrition the enemy. Also make sure the enemy can't just go around the defenses that took you a hour to finish, and Unmanned defenses that aren't just dedicated to delaying is the least efficient defenses you can create. Manned defenses, however, will double the amount of time it takes for a enemy to get through, with the side benefit of dealing damage and dwindling numbers.
Walling Off
There are situations where an enemy will be attacking on your flank, and you don't have enough forces to both defend and hold the various front lines and hold this new one. You, with at least one hivelord, can just spend a ton of plasma and wall it off, to buy time for you to impregnate enemies but also to delay the enemies.
Stage 2
Congratulations, you have successfully stalled the marines into a attrition war. Marines to Xenos ratio is now looking more favorable, maybe about 2 Marines to 1 Xeno, but preferably less. You are now able to push back the marines and reclaim. This stage of the war is CRITICAL. If you fail and don't retreat effectively you may lose many Xenos and die. If you are the Queen, if you believe you are unable to defeat the Marine's front lines continue the attrition instead. After reclaiming the land you lost that isn't that heavily defended, then you must move onto the defenses that the Marines have set up close to the Front Line. This, is Critical and is the tipping scale that will either let you advance to the FOB or get annihilated. Remember earlier where I said Marine defenses were limited by time and getting metal? If its 1, 2, or 3 hours in they will have that amount of metal, set up turrets, lots of defenses, mines, and everything.
Which is why they assume the Xenos attack them next, and that is why you don't attack them immediately unless you are certain you can win this battle. One of the benefits after reclaiming back Space is that you often are able to go around and attack other locations. Kill Telecomms? That makes it very hard for them to work and get orders out and Information back up. See if you can raid a FOB? Sure, assume it is only slightly less defended as the Front line defenses. Do not say "Screw everything and attack their fort near the front lines", continue the attrition war and see how many marines you can pick off when they sent all of their squads at the Hive. Abuse the fact their numbers are low. Think outside of the box with guerrilla warfare. When your ready, execute the assault on their base near the front lines, supply lines, or their FOB. With low numbers, the supply lines aren't heavily guarded, so attacking that is a good idea too. Push your advantages wisely. They can't fight without Ammunition for their guns, and there are only 3 supply beacons per squad leader by default, and probably 2 of their squad leaders are dead. Eventually, after your siege on their table fort, push your assault at their front line fort and annihilate. You've taken most of the planet. Good job. If your attack on their front line fort is failing, order a retreat as fast as possible and minimize casualties. You could lose from a failed assault on their front line fort.
Stage 3
Stage 3 begins the second you've pushed them back to the FOB. You are putting in the hurt now. Marines to Xeno ratio may be as low as 1 marine to 1 Xeno or maybe even less! Really, you can begin the curbstomp, the FOB didn't stand a chance really. Don't rush in too fast though, as it is possible you can lose still and be pushed back, but if you outnumber 3 Xenos to 1 marine you basically have already won. Attrition if necessary and siege the FOBs. If they retreated back to the station and essentially abandoned the FOB like everyone should do, instead look at Stage 3.5.
Stage 3.5, or "Cowards with marines left"
Stage 3.5 begins any time the Marines have retreated back to the ship. If they still outnumber at least 2 Marines to 1 Xeno, delay your assault. The problem is that while you could trump these marines before with free movement and the ability to flank, If you go on in a dropship into the ship you can be surrounded and potentially killed off via explosives and other weaponry. While you could potentially defeat them, it is better to instead allow evolution to T3s and finish evolving to the max. Once your evolutions are complete, then go at it.
However, if it is more like 1 marine to 1 Xeno, still be cautious, but you will probably absolutely annihilate them if you rapidly assault the ship. Without time to prepare defenses, they won't stand a chance with your numbers unless you are really behind on evolution.
Really, this is indeed a dilemma that is often solved by the Admins for you, but if it isn't do find yourself in this situation, pause and think about this tactical choice whether to attack or to wait. This is a Critical stage really, so don't take too long. These are guidelines too. Often marines can be really good or really bad. Good luck either way.
Stage 4, or "Footholds on the Ship"
Welcome to stage 4. You successfully have attacked the ship have taken it over. While I doubt we even need a section for this, here is a list of objectives in order of priority.
- Make sure the self destruct isn't activated. It takes 20 minutes to activate I believe. Self Destruct disabled for non-events now.
- Inevitably when Escape Pods happens try to see if you can't stop them assuming you don't successfully annihilate the CIC first.
- Kill the CIC and its commmanders, as cutting off the head of a dying snake will ensure its death.
- New Objective: Make sure that the reinforcements that come in from distress beacons don't screw you over. I saw a Xeno Game where the Xenos basically won the ship and CIC but escape pods occured and the distress beacons actually started wiping out their force. That was insane.
- You must absolutely make sure that the marines don't get a chance to set up defenses ship-board. Doing so may cause SD draw from the ship blowing up after 20 minutes of crashing into the atmosphere.
- Kill all remaining humans.
Stage 4.5, or "Footholds on the Ship but there are marines left this time."
Stage 3.5 succeeded, but there are still marines on-board the ship, and they are actively trying to self-destruct the ship. Remember what I said about how Marine defenses worked? Marine Engineers need time and more importantly, metal, to set up defenses that could possibly let them defend against superior numbers and quality. Zerg Rush the Self-Destruct and disable it ASAP. If you succeed, move onto Stage 4.
Congratulations, you have completely wiped the Marines off the planet and stolen their ship. The Great Mother will be proud of you.
Edit: Changed Recovery to Warding for down and fire. Do remember to bring crit Xenos out of the line of fire. Also use Hotkey mode to switch between Harm and Disarm intents. Without Hotkey mode: Ctrl 2 for Disarm, Ctrl 4 for Harm. With hotkey mode: 2 for disarm, 4 for harm. Xenos also have Information as a resource but not its not really all that important. Help-Intent clicking on Xenos on fire is a thing you should do unless they are in the line of fire (even if you are blocking shots unless you are a complete tank.
My final advice?
I saw a game. A Xeno sabotaged us and let the marines through the podlock. We got stomped (due to a Xeno griefer who melted a vital access point for the Marines open.. I was dead. 8 of us were left vs 100s of marines...
Then via boiler, well positioned quick-defenses and robustness the Xenos forced the Marines to retreat during the last stand of the Aliens.
Defeat is a State of Mind. Morale is absolutely a thing you have to worry about, no matter what team you are on.
Edit: They lost due to larva suicide since the marines were so toxic that they failed to kill 8 Xenos after wiping all the others ones off the map. It somehow was still close.
Edit 2: Then the marine's ship got Self-destructed by an "accidental" engine failure from a low chance malfunction.
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