A Guide to Standard Zerg vs Terran: The Mid Game

In part one of this guide, we looked at three "standard" openings that a Zerg player can perform against a Terran opponent. While each of these openings might be relatively different from the others, they are all designed to allow the Zerg player to reach a point where he can move into the midgame with a good foundation. By the time your lair is done, you should: 1.) Have two evolution chambers and be researching Melee Attacks and Carapace. 2.) Have a Baneling nest. 3.) Have taken at least three gases. 4.) Have a third either completed or building.

Once your lair tech is complete, most zerg players find themselves faced with the most pivotal decisions in the game, namely what tech path to pick. Because Zergs are more of a reactive race than the other two, what you decide to do for the midgame is often dictated by the composition you scout your opponent trying to use. This may be difficult to tell, but by the time your lair is complete you should have a decent idea if the Terran player is going pure bio-medivac, tank-marine, or mech. I'll structure this guide by going through the appropriate Zerg responses to each of the standard Terran unit compositions.

Pure Bio-Medivac
If your opponent is going for heavy upgrades with marines and marauders, with medivac support, you know that he is most likely going to be playing a tankless game. Another queue that might clue you in on the Terran working towards this composition is that he may use the factory to scout once its been used to make addons for barracks and starports. This build may seem easy enough to deal with at first, but can be deceptively strong if executed correctly, as it is surprisingly mobile.

Banelings don't necessarily automatically counter it because good Terrans can theoretically micro only marines back and then split them. Banelings are not cost effective against marauders, and aren't even great against marines unless they trade at a 1:2 ratio with marines at least. If you've had an early game where you've needed to use slightly more gas than you'd like, this is a good composition to go with because infestors in small numbers are more effective than mutalisks in small numbers.

Against the pure bio-medivac composition, you have several options. Infestor-Ling-Baneling is probably the best bet against it. Many players favour Stephano-style play, where the Zerg relies on upgraded lings and infestors to hold off Terran pushes while teching towards a faster hive. I feel like this can work, but that many Terran players are getting more savvy to it, and that in order to really trade cost effectively with a Terran using the pure bio composition, you need banelings.

Back before the infestor buff, fungals were used mainly as a snare, and when the damage was increased it was used more as a replacement to banelings as a source of AOE damage than as something to complement banelings. Remember that Starcraft is not merely a game about battles, that it is also heavily about economy. While it certainly isn't a bad thing to crush a Terran army, it should always be noted that a pure bio army is as cheap as Terran armies get, and it can be easily remaxed, so simply trading an avalanche of speedlings and infestors to kill a Terran bio army may work, but it may not be cost effective.

Fungals are still viable as a snare

As long as the Terran kills his fair share of your units, and has a strong economy to rely on, he may very well end up winning a protracted game if he has better mechanics than you, and is able to keep trading efficiently, because it is more likely that the zerg player will run out of larva (Speedlings are very larva-inefficient) than that the Terran will run out of production. Long story short: Banelings are a good idea to include in this composition.

In order to properly reach this composition, you'll need to rely purely on upgraded banelings and speedlings until you are able to make 5-8 infestors, generally if you add more its in the late game, though with 8 infestors you should have more than enough fungals for anything. If you plan on harassing with burrowed infestors and infested terran bombs, then feel free to make more, but 5-8 infestors feels relatively standard. Start your infestation pit as soon as possible, and research pathogen glands as well. When pathogen glands has been researching for 30 seconds, you can begin to make infestors and they'll pop as soon as the upgrade finishes up.

With this composition baneling speed is also a must, so get that too. You should be operating on at least 6 vespene geysers to make this work, any fewer and you simply won't have enough gas to sustain it for long enough. When you've gotten all your lair tech upgrades started (Baneling speed, pathogen glands, +2 melee and +2 carapace), and once you've built enough infestors for you to feel safe, then tech straight to hive. If you crush a push, take a new base, this is a safe rule of thumb with all compositions in the mid game.

Execution in engagements is of paramount importance with this composition. You shouldn't have more than around 35% of your lings as banelings unless the situation is very dire and you really need to defeat the incoming Terran wave. If you know your opponent is all-in and all you have to do is survive the next push to win then by all means make more banelings, but generally this won't be the case, and banelings are very costly units to lose unnecessarily. When you engage, if your opponent is bad you'll just roll over him, fungals on the bio army with banelings connecting and lings to clean up are devastating.

If, however, your opponent is good, it is quite likely he'll CRTL-Select his marines and micro them back, and then begin splitting them, leaving the marauders and medivacs infront. If this is the case, it is crucial that you CRTL-Select your banelings, and make them simply move past the marauders in order to connect with the marines, while managing fungals as best you can. Single-control-group-syndrome is not your friend. Make sure your infestors are separately hotkeyed, you must not lose infestors.

Notice that banelings were selected during this engagement

If you're playing at a level where your opponent is able to micro his marines in such a manner, there should be no reason why you can't respond in kind by microing only your banelings forward, and splitting them up to attack marines. Banelings against marauders are terribly inefficient, and lings do well against them. A-move your entire army in, throw down a few fungals, if your opponent micros his marines back, micro your banelings forward.

Lings will be attacking everything, but you need to manage your banelings and keep your infestors back as much as possible. Your priorities should be to keep infestors alive, to make sure you're being cost-effective with your banelings, and just let the lings kill what they can. I've probably repeated myself a good deal in this paragraph, but the importance of execution really is of great importance with this composition. It is slightly harder to execute than simple Ling-Infestor, but infinitely better if done correctly.

As an added side-note, it should be mentioned that Terrans opting for the pure bio-medivac composition are far more mobile than a regular marine-tank composition. If you choose to go for infestor-ling-bane as a response, it is a good idea to throw static defense down around your bases. Usually people make spine crawlers in each of their bases, but many Terrans, in anticipation of this, simply micro around them and do what damage they can, and then leave with the medivac intact.

I've recently started making spore crawler walls and leaving around 10 speedlings in each base. Spore crawlers ensure that if he decides to drop, he won't leave, and the speedlings are able to kill all the marines provided that they get a surround on each marine as it drops out of the medivac. If you're taken by surprise and the Terran is able to unload all the marines before you catch them, you'll need more than 10 speedlings to kill it off. I personally prefer using spores, but this really is a matter of personal preference. It should go without saying that you need to surround your bases with overlords so you can be more aware of incoming drops.

Marine-Medivac-Tank
This composition was, for a good period of time, the go-to composition for most standard Terrans. Unsurprisingly, Muta-Ling-Bane was a standard response by most zergs. While it is also possible to use infestor-ling-baneling style against this, mutalisks, when used well, allow you to punish poor positioning the best. You don't want to skip your upgrades, and you want to place your spire as soon as your lair finishes.

Start stockpiling gas and make sure you aren't supply-blocked by the time your spire finishes, and as soon as it's complete, make as many mutalisks as you can, this will usually be between 7 and 11. From here there are two options. You can either commit more fully to mutalisks and use them as powerful harassment options, thereby delaying your hive tech and playing a longer midgame, or you can make only around 15 mutalisks, enough to give you map control to shut down drops and to harass with relative effectiveness, and then tech to hive behind them.

If you choose to commit to mutalisks, then you should get the air upgrades. Get the attack upgrade if you plan on harassing more, and the armour upgrade if you plan on fighting with them.

Small group of mutalisks used to shut down drops while teching to hive

Again you don't want too many banelings, because against any tank compositions lings are surprisingly effective not only at killing tanks but drawing friendly fire with marines. If you can draw splash damage, you can actually trade quite efficiently with lings. The same heuristic rule of not making more than 35% of your speedlings into banelings seems reasonable here. Mutalisks are units that allow you to truly outplay your opponent. A good mutalisk player can force his opponent to be in multiple locations at once, allowing you to simply outplay your opponent as your mechanics kick in and allow you to eke out an edge.

When using this composition, you need to remember than you lack the same head-on attack power that you'd have if you'd gone for infestors, so you really need to poke around as the push is coming, forcing sieges, picking off whatever you can, especially reinforcements, while you build up an overwhelming army and set up for a flank. Once the Terran sieges up, poke in with the mutalisks and pick off any tanks you can, but don't ever commit to the point where you'll lose more than one. Use the mutalisks to get a good sense of the perimeters of the siege position, and when best to engage.

When you finally do engage, it is best to do so with a flank. Once again if the Terran doesn't micro his marines back, he'll be crushed, but if he does, you need to make sure your banelings don't all roll into tanks. A-move with your entire army, making sure your mutalisks are in a position where they'll be attacking into mostly tanks and very few marines. CTRL-Select your banelings and make sure they connect with the marines as well as possible. Don't lose mutalisks, make sure you keep as many alive as possible. If your opponent has mixed thors into his army (it is becoming increasingly popular to do so), then magic box it and adjust accordingly, it will most likely be with the tanks and certainly won't be microed back with the marines, it simply isn't fast enough.

Notice that the banelings are being controlled to chase marines while the lings attack-move

Remember that mutalisks really allow you to dictate the flow of the game and to outplay your opponent. Mutalisks, when used well, counter this composition better than Infestor-Ling-Bane, but if you feel unconfident with your mutalisk control (there is nothing wrong with this, many great players do, Stephano admits he is very uncomfortable with mutalisks), then feel free to use Infestor-Ling-Bane.

The execution is essentially the same as it is with the pure bio-medivac composition, but you may choose to burrow an infestor and drop infested Terrans around the tanks to draw tank shots, or you could catch the tanks unsieged with a fungal. Just make sure you keep your infestors alive (tanks are very effective against them), and that your banelings connect with marines.

Mech Plays
Mech plays are very troublesome for many Zerg players. A good mech-Terran can be an absolute nightmare to play against. In general you need roaches, because any decent mech player will go for blue flame hellions for some form of early game harass (Terrans often feel terribly insecure against a Zerg opponent who has been able to macro unimpeded, and for good reason). Usually a player will reveal that he is meching before your lair tech is done, so you'll know in the early game if he is going for a mech play.

More than 4 hellions usually signals some sort of a commitment to mass mech production, and it is wise to invest in a roach warren if you see anything more than the standard 4. If you scout mech, you may want to researched ranged attacks upgrades rather than melee, and be sure to get the speed upgrade for roaches, and even the burrow movement and burrow upgrades. For a meching player, there are several styles that each require their own particular counters to effectively deal with.

Hellion Thor
Many mech players actually opt to go for an early hellion-thor push to your third base. This can be very difficult to hold, but in general against this composition you need to go roach-speedling-baneling. If he has too many hellions, make more roaches, if he has too many Thors, get more lings, and make only enough banelings to kill any repairing SCVs and just to deal some extra damage. Your army should generally be 50% roach, 10-15% baneling, and 35-40% speedlings. If he has blue flame hellions in large numbers then just mass roaches. If the game goes on later and he still opts for a tankless mech composition, then it is a great idea to get an infestation pit with pathogen glands and neural parasite.

Neural parasite used be an incredibly good spell, then after the range was nerfed it was somewhat forgotten. Against hellion-Thor, it is still ridiculously good. No siege tanks will outrange you and slaughter your infestors, and Thors are actually very dangerous if the Terran gets a critical mass, because they just murder roaches, especially with SCVs repairing. Hellions don't do great against infestors, and fungals will keep them in place as the roaches move in. Neural parasites on the Thors shut down a huge portion of the Terran's damage output, and allow you to partition his army, fighting only a bit at a time. Neural parasite as a counter to Thor-heavy compositions is not something any Zerg should overlook.

A group of thors that would usually tear through my roach count is easily dismantled by using neural parasite

Standard Tank-Hellion-Thor
If your opponent goes for the standard tank-hellion-Thor, it can be difficult to attack. Generally you don't want to attack into any sieged Terran position. If you do, however, do so with overwhelming numbers and a good flank. Generally all you can hope to do against this composition is to clear up a good portion of his army, but not all of it. If you do, then you need to be ready to tech switch behind the initial attack.

You need to have a very strong economy - the lack of harassment options for a mech terran should allow you to establish a relatively early 4th and to saturate it - and you need to have a tech switch in mind. If you attack and clear out all the tanks, then roaches become much more effective. If you kill all the hellions then get slightly more lings in the next wave, but make sure you attack again soon after (hellions reproduce fast).

If you kill all the Thors, he'll have nothing left that shoots up, and Thors take so long to build that you should be able to pick off a good few units before he gets them back up, and you can also use them to harass for a while because he won't have enough Thors to cover everything for a good period of time.

Mutas used against a mech Terran with low Thor count

Don't commit too much to mutalisks, remember that anything more than about 4 Thors almost completely negate them. In general it can be difficult to break this composition in the midgame and you need to try to weaken it while trying to stifle his economy. Delay bases for as long as possible, and keep weakening the army in a cost-effective manner. If you see him pushing out engage as much as you can when the army is unsieged, and also abuse the Terran's immobility by countering.

Roach-baneling used against mech

It is usually very difficult to end a mech game in the midgame, and you need to delay and weaken the attacks for as long as you can until you get brood lords up, which, as it turns out, is a perfect segue into the next part of this guide! Coming soon: ZvT Late game. Hope you enjoyed this, and please leave any comments, questions, or suggestions!

 

Special thanks once again to Saikou who sent me replays of him playing against Terrans with Mutalisk style ZvT, which I've somewhat abandoned. Cheers!