http://forumserver.twoplustwo.com/181/s ... -a-847811/
 
I wrote this guide because there's not a lot of good information out there right now. The best material is scattered between random forum posts and high-level replays, so this is an attempt to produce a compilation of some known info as well as things that are not out there quite yet. It is certainly not comprehensive; that would take way too long. Included are "cookie-cutter" strategies that are simple enough and effective. I use all of these strategies and highly recommend them. Over time they may become less strong as more things are discovered about SC2, but for now I believe the material is top-notch.
 
My character name is Fistdantilus, and I'm a Rank 1 Diamond player on the US server. I'm not spectacular, just good enough at the moment. I got beta for exactly one day, so all this knowledge is from 99% retail play.
 
This guide assumes you're familiar with the basics and mechanics for the game, so I won't go over them. In fact, here is an amazing "all-in-one" zerg guide.
 
Section 1: Early game
Section 2: One or two bases?
Section 3: Overlord placement and sacrificial scouting
Section 4: Scouting, how to interpret what you see
Section 5: Strategies vs each race
Section 6: Tips and tricks
 
Section 1: Early game
 
9 Overlord  
Send scouting drone at 12
13 Spawning Pool
13 Extractor
14 Overlord
Save larvae
4 Zerglings + Queen when pool completes (should have 2 larvae with one more about 5 seconds later)
Take drones off of gas after 100
Drones
Hatchery around 20-22 food
Overlord around 20-22 food
Put drones back on gas sometime after first injection larvae pops
 
That's the build I do almost every game, and there are many reasons for it:
9 Overlord is better than 10 Overlord or extractor tricks with regards to economic development. Here is a thread which times out a ton of build permutations. TLDR version: 9 overlord > all.
13 Pool is roughly 5 seconds faster than a 14 pool, which makes a big difference against proxy gates or 6 pools. It also means 5 seconds faster on zergling speed or a baneling nest, which is very important in the mirror. The hit to economy is negligible, especially since you can recover so quickly with simultaneous drone production.
4-6 zerglings in the early game can greatly help against early "cheese", and sometimes you'll stumble into an easy victory when your opponent lets them into his base or gets his first zealot surrounded. It does happen!
Start by hatching 6 zerglings every game until you get more comfortable with Zerg as a whole, then try cutting back to 4 or 2. When your zerglings pop, kill or shoo away any scouting workers your opponent has in your base. Then, go to your natural expansion and shoo away whatever workers they may have there as well. This is a benefit to 13 pool that a very early hatchery build doesn't have: the ability to start your expansion without worker harassment. Next, send your zerglings toward the enemy base. This process from hatching to clearing to attacking should happen very quickly. The better your opponents are, the greater the chance you encounter some type of wall-in when your zerglings reach the enemy base. This tends to make your zerglings ineffective at attacking, but great for scouting. Park them at the front of your opponents' base and near Xel'Naga watchtowers. React quickly to save them if they get attacked, because they're your only defense for quite some time!
Use the zerglings to peek up the ramp to look for any buildings your opponent built in sight range. They may give away key information allowing you to not sacrifice your overlord.
 
Is it the most optimal build in all situations? No, it isn't. But this is the build that will allow you to be competitive in every single game, and that's honestly all I want from my opening. It can handle all types of "cheese", and quickly go macro if you see the opportunity.
 
Section 2: One or two bases?
 
Two*, for a very simple reason: you can't produce enough larvae with a single hatchery. Even if you don't saturate both bases with drones, you'll see an immediate lift in economy by splitting up your workers between main and natural. This is because there is less competition for mining time between each worker, allowing greater efficiency.
 
I generally discount one base tech strategies for Zerg because of the relative lack of effectiveness. Terran and Protoss have viable tech options because these options can create so much damage for a very minimal investment. For example, a single cloaked Banshee can destroy an entire mineral line. Likewise with a dark templar, siege tank on a cliff, or immortal drop with warpgate tech. Preventing each one of those takes a very specific approach as well as a lot of time. Single base muta harassment isn't very feasible because it's stopped by marines and stalkers, units your opponent has been building since the beginning of the game. Burrowed infestors are stopped by a simple cannon/tower at the choke, and straight tech to broodlords or ultralisks is completely out of the question.
 
*There's a caveat here: on certain maps against terran you're walking into an auto-lose if you expand early. Detailed in the ZvT section.
 
Section 3: Overlord placement and sacrificial scouting
 
Overlord play is absolutely crucial to success.
 
Your first two overlords always have the same goal against Terran and Protoss: position themselves on each side of your opponent's base, out of range of any marines or stalkers. While very easy to do on a 2-player map, on a 4-player map it's more difficult. Start by sending them separate ways while you scout with a drone. As soon as your drone finds the enemy, re-route your overlords to head into position.
 
Use the remaining overlords to overlook expansions or key areas around the map. Tend towards putting them hovering over space so as not to die to wandering marines. All you need to see are the minerals.
 
Against other Zerg it's slightly different: you want to place an overlord in front of their base to see troop movement. If a queen tries to walk off-creep, it's basically "L-O-L turtle race" where your turtle should safely cross the road. Also, place one outside of your base to spot banelings morphing.
 
So… the overlords are hanging out in space around my Terran/Protoss opponent. Why is this important?  
 
Because you need to sacrifice one or both of them once your economy is stable. This generally means around 30 food. Your 2nd hatchery will be up and going, and you'll be teching and/or making another queen. You have no choice but to do this! Fending off a 4-gate push is vastly different than a void ray rush, as is holding off a bio-ball versus hellion play, etc. And of that 30 food, you basically have 4-6 zerglings as your whole army.
 
So I heartlessly sent my overlord to be brutally murdered. Now what?
 
Now you react to what you saw. Not only do types of buildings and building activity give away information, but the units that killed your overlord give valuable intelligence too. Here are some of the tell-tale signs for Terran and Protoss and what they mean. How to react is covered later. Be sure to know the building and research animation for each structure.
 
Section 4: Scouting, how to interpret what you see
 
Protoss:
 
No assimilator or has 2 gateways: 2-gate rush
 
Stargate: Phoenix and/or Void Ray rush
 
3+ gateways: large push coming
 
Robotics facility: can be part of a gateway unit push, like gateway units plus collossi/immortals
Sidenote: observers likely following your main army
Twilight Council: look at the units your opponent is making:
Primarily stalkers: blink tech
Primarily zealots: charge
Roughly even mix: dark templar and/or high templar
The number of gateways and warpgates you see also makes a difference:  
no warpgates means he's saving gas which leads me to believe rushing dark templar
more gateways/warpgates means he's going to push and/or expand while bolstering an army with templar
 
Look at the types of units that kill your overlord. Protoss will always have stalkers, but they won't always have sentries. Sentry presence indicates going for more stalker/colossi heavy armies rather than zealot heavy as the force fields restrict zealots too.
 
Check to see how much chrono boost your opponent has and what he's using it on. If he's using boost on gateways, it's pretty obvious a push is coming. Others will use it on key upgrades like the Thermal Lance or the attack upgrades. In the very early game when you scout with a drone, stored chrono boost is a sure sign of a 2-gate rush.
 
 
Terran:
 
Factory: look at the attachment
None: possibly too early to tell, possibly only 1 hellion harass
Tech lab: siege tanks, possible Thor
Reactor: strong hellion harass
Armory: Thor, possibly thor-drop
 
3+ Barracks: Bio
 
Barracks with an early tech lab: Reaper and/or Bio, though could be just for a building switch later
 
Starport: Viking, Banshee, Drop
Surrounding units/buildings will clue you in if it's a drop: multiple marines/hellions and/or an armory being built usually means drop. Few units means opponent skimped on defense to produce faster Viking/Banshee/Thor
Look at the amount of units that kill your overlord, as this is a very telling sign from a Terran. More than 4 marines is a dead giveaway of a strong bio component to their army. If they try to only use 1-2 marines to kill your overlord, you'll see their whole base anyway by the time they kill it.
 
 
 
Zerg vs Zerg mirror match
 
Banelings define this matchup, and you have to get good at baneling play. There is honestly no other option, even if you intend on always going roaches. This is because you have to understand the mechanics behind banelings in ZvZ to both succeed with them and against them. I'm not going to cover 15 hatch or roach openings, simply because it would take a novel. Banelings are very strong all in all levels of play, and it's the easiest strategy to execute.
 
Defending against a 6 pool
 
The 6 pool will arrive roughly 5-7 seconds before your first zerglings hatch. Run your drones away while you wait, but don't be afraid to attack with them. If they brought a drone to offensive crawler you before the lings arrive, attack it with 4-5 drones while it builds. Keep making zerglings. When you attack with your lings, also attack with your drones until you have enough zerglings to survive and/or your queen pops. With a little practice, it's actually fairly easy and kind of fun. After holding it off, proceed to the baneling plan with a huge advantage. Your opponent has to kill 5 drones just for you to be even in number with him, so don't be sad if you lose a few: there's a good chance you're still ahead!
 
Roach opening vs Baneling opening dynamics in ZvZ
 
There are people who really hate baneling play in ZvZ, and have devised early roach openings to avoid exploding bug micro. The theory goes that roaches are strong against zerglings and are largely unaffected by banelings, making them ideal for dealing with both. In a straight-up fight that's completely true, but it doesn't work that way in practice. Here are some things you should be aware of:
Roach players have to skimp on early zerglings. This makes it very easy to snipe the queen with your first 10 zerglings as he'll have one spine crawler and maybe a few zerglings. If you snipe the queen, you can pull back and tech to lair while you drone up and expand since losing the queen sets him way back. This is the most common way that I win against roach openings, even though converting this advantage to a win takes awhile.
Some maps lack a small choke point, allowing zerglings to stream through and hatch banelings inside their base.
The roach player can't leave his base. Remember what I said about having an overlord to monitor troop movements? Well the second your opponent leaves with his roaches, you immediately run into his base and kill everything. Zerglings are so fast that you'll even have time to come back and defend!
Roach openings only equalize if done correctly: they rarely lead to an immediate win. Basically, you have to have perfect play just to be on even footing with the baneling player. If you slip at all, one baneling explodes your entire economy.
Roach players do have the option of playing "sim city" where they build their spawning pool, roach warren, and spine crawlers in such a way so that you have to run your banelings the long way around. First and foremost stay away from the spine until necessary, and use the creep if you can for the speed boost.
 
Use the same build order (13/13), except don’t remove drones from gas and don’t stop making zerglings after your pool completes. Research zergling speed as soon as you reach 100 gas, then put down a baneling nest as soon as you reach 50 gas.  
 
Baneling play
 
The theme of this matchup: only attack with your zerglings if you're going to gain some concrete advantage. Don't engage his lings with yours unless you have a numbers advantage. Never just attack-move into his equal zergling army, ensuring they all die. Keep them alive and active, and give your opponent chances to make a mistake. All you need is one baneling hit on your opponent and the game is over.
Gain control of the enemy ramp. This is usually pretty easy because your opponent will mistakenly build a spine crawler or drone after his spawning pool completes, which means you'll have a numbers advantage. It takes 11 drones on minerals to constantly produce lings and overlords from one queen+hatchery, so making more drones doesn't help. After your pool completes, it's nothing but zerglings. You'll need to get good at making zerglings and doing injections through hotkeys and the mini-map only. No clicking back to your base, because it's constant micro from here. Gather at his base and set your rally point there.
Morph banelings: as many as you can, hopefully out of sight range. If your opponent tries to kill your morphing banelings, use your zerglings to snipe his queen.
Select all your banelings and right-click move them into the mineral line. DO NOT A-MOVE as they will explode on first contact with anything. Your opponent's army will be pounding on them and you don't want them to be wasted. The ones that die will kill everything nearby anyway. At the same time, move your zerglings around and do what you can (remember, NOT by just attacking other zerglings!). Since banelings get a speed increase on creep (and drones don't!), the banelings will catch the drones if given enough time due to the computer controlling your pathing while the opponent has to path his drones manually. Just keep chasing the drones. 7 times out of 10 the game ends here, or he loses significant drones and limps along until you kill him later. Swearing often ensues.
 
"What if I didn't do enough damage?"
 
Not a problem! If you have 15+ zerglings left, retreat to the nearest Xel'Naga tower or somewhere you can back-stab from. If you have less left, retreat to your base. By now your first overlord should be in front of the enemy base so you can see what is going on. If you have significant numbers of zerglings, just run them into his base if he tries to leave with roaches. If he wasn't going roach, hatch a few zerglings and morph them back at your base, preferably near the ramp. 6 should be more than enough. They sit at the top of the ramp because enemy zerglings often charge up there blind and mass-explode. At this point there are roughly two paths to take: upgrade to lair to get mutas or start making roaches. Muta is better, but going straight for roach/hydra is okay too.
 
An important thing to note here is that even if you fail in your baneling attack, you're not too far behind. You have roughly as many drones, a queen, and steady gas intake. With the next injection larvae make all drones if you can and work towards lair.
 
Mutas are all about map control. Hydras and queens are ridiculously slow off of creep, so backstabbing with lings/roaches/muta is very easy to do as well as picking off units that get too far away from the hydras/queens. Constantly look for holes in your opponents' defense, and use all available gas for mutas. Use the excess minerals to expand and keep massing. Protect your expansions with spine crawlers, and put down a roach warren. At some point, ling/muta won't be enough against roach/hydra in direct combat and you'll need roaches. You'll also need... banelings! Upgrade the speed, and generally only use them for defense. When your roaches engage theirs, run the banelings at the hydras (try to be on creep for this play; that's why you use them defensively). After taking out a significant portion of the hydras your mutas can engage.
 
If you're going muta, you want to only use creep tumors to link your bases and prevent creep tumors from your opponent because hydras/queens are terrible off creep. If your opponent is building a creep highway outside of their base, morph an overseer and destroy the tumors. Slow hydras/queens can't leave their base, helping your map control.
 
Let's assume your opponent will reach lair first. It's definitely more difficult to win, but certainly not impossible. The first problem is expanding, which is solved with queens and spore crawlers. Extend the creep out from your base with the help of several queens (you're going to have excess minerals). Build spore crawlers inside your base, then move them to the expansion area and start building your hatchery. It sounds like a long and painful process, but you only need 2-3 spore crawlers and 2-3 queens.
 
I'm partial to going heavy muta rather than roach/hydra because the mutas can cause so much chaos and have total map control. Roach/hydra does work, but it's very difficult to pull off. Assuming you have map control and are able to take a third expansion, start upgrading to hive where you'll go for broodlords.
 
I'll reiterate one last time: the mutas are for constant harassment. Pick off overlords, snipe queens that get too daring, creep tumors, zerglings, whatever. Be the biggest jerk you can be with those things.
 
Other options in Zerg vs Zerg:
 
Infestor: I can't decide on the value of fungal growth in roach/hydra fights. I'm certain that getting upgrades makes more of a difference than fungal growth, so get these after you're already 2/2.
 
Zerglings: just a waste of resources against roach/hydra in a fight, but still useful for randomly ganking expansions and scouting.
 
Drop tech: There's no point as you can walk into your opponent's base anyway.
 
Replays:
 
Example of an easy baneling win:  
 
 
 
Here's a typical example of how the game goes if one player gets mutas first:  
 
 
 
Zerg vs Protoss
 
A very fun matchup; also considered to be very balanced. One quick note is that there's generally no retreating by either side early in the game. Zealots can't out-run anything, and roach/hydra can't out-run stalkers off of creep. Sometimes there are opportunities to sacrifice a unit or two by running them into the pursuing attackers, thus saving your main army, but a lot of the time you just have to fight it out.
 
There are several good strategies against zerg:
 
2-gate: 2 early gateways go down, chrono-boosting out 5 zealots and attacking. Very strong in general, but fails to early roaches.
4-gate: 1 early gateway for protection, then churning out 3 more gateways to pump units and attack. Very strong, but has to be all-in to be worth it. Possible to transition out of it if protoss did enough damage.
Robo rush: It's like a 4-gate, but with 2 immortals instead of other stalkers/sentries/zealots. The immortals are there to rip through your spine crawlers and roaches. If I lose to a strong push, it's usually this.
Stargate: Void Rays and/or Phoenix.
Forge expand: Early forge with cannons to expand.
 
How to deal with them
 
2-gate: Against protoss I alter my build slightly. Pool on 13, extractor on 15 (though 13/13 is just fine too). The reason is because I'll put down a roach warren soon after the pool completes and I need the extra minerals. I generally kill the scouting worker before putting down the roach warren. The zealots will arrive shortly before your first roaches pop, but it's OK: the queen and your 4-6 zerglings can delay them. And once the roaches pop, the jig is up. Kill the zealots and counter-attack. While you might not win the game right here, you should kill far more than you lose. While it's possible to rely on zerglings to defeat the 2-gate, it takes a lot of effort and larvae. Not only that, but with zerglings you have a very high attrition rate: you're going to steadily lose them as your opponent loses zealots. With roaches, you make 4-5 roaches and zealots are shut down near-permanently while you lose nothing.
 
4-gate: Using the 13-15 build as above (just in case it's a 2-gate or the rush comes early), proceed as normal. Park your zerglings outside of his base and at other key areas while you expand and make more drones. Once your hatchery is finished, make another queen and start producing 2-4 spine crawlers. This is about the right time to suicide an overlord into your opponent's base to check his troop count (and is usually when you find out it's a 4-gate). Change production to zerglings/roaches and upgrade speed for both of them. While I like roaches earlier in the game against zealots, I prefer more zerglings for the middle-game against protoss because he'll be so stalker heavy. The zealots will die very quickly to the spine crawlers and roaches, leaving a very stalker/sentry heavy composition which favors having more zerglings. A 4-gate must be all-in from the protoss player, because if they chicken out and try to run, you just surround them with your lings and decimate them.  
 
Robo rush: It arrives at the same time as a 4-gate, only this time with either a Colossus or 2 immortals (I believe the immortal build is tougher). Pretty much the same as a 4-gate except that you want to be sure and have more zerglings in your mix, and you can't rely on your spine crawlers as much.
 
Stargate: Generally very weak if you scout it. Queens are better than spore crawlers against void rays, but it's the opposite against phoenix. In general, assume void rays and get 4 queens and a hydra den. The strongest variation of this build is to attack with 2-3 void rays instead of sending them one by one. If you spot a stargate, make sure you link your bases with creep if you haven't done so already and start saving up energy on your queens (both over 50 is ideal, but don't stop injecting permanently). It's a backbreaker to protoss if both of your queens can transfuse, and you don't really need the larvae to prepare against a void ray rush anyway. When the void rays come, bring both of your queens before engaging and focus on one of them, transfusing when needed. A quick ling/roach/hydra push soon after should seal the deal as his ground forces will be too weak. Or, take a 3rd, insta-saturate it, then start the pressure. The weakness of this strategy is why I don't gas-steal against protoss. Please tech to void rays, please!
 
Forge expand: You can either all-in baneling bust it, or just pump drones. The advantage of a bust is that he'll have close to zero defense once you get past the cannons. The disadvantage is that if it doesn't work, you're pretty boned. Pumping drones leads to a middle-game where the protoss has an equivalent economy, which makes him dangerous. Take a third before saturating both bases because larvae is going to be the big bottleneck, and keep tabs on his army size with sacrificial zerglings and overseers. It's crucial you don't forget to scout him often because protoss can macro up a dangerous army very quickly on two bases. Sometimes it's map dependent: all-in ling/roach works extremely well on Blistering Sands or Kulas Ravine because you can circumvent the cannons.
 
Key unit analysis in Zerg vs Protoss
 
Zerglings: Zerglings can either be very useful all game, or quickly become obsolete and it's entirely up to the protoss player. Once the protoss is ahead in attack upgrades versus your carapace upgrades, it's time to let these guys ride the pine unless the protoss army becomes too stalker/immortal heavy. Being able to chrono-boost the attack upgrades could mean these little guys don't see action. Very good against stalkers and immortals, and good filler overall.
 
Baneling: Not useful unless busting. 4 to take down a cannon, 5 for a pylon, 10 for a forge, 13 for a gateway.
 
Roaches: These will be the backbone of your army from beginning to end. Psionic storm? Roaches don't care about psionic storm with their nice HP. It would take 2 storms to kill these guys, and the battle will be over by then. Colossi? Roaches only care about 4+ colossi, because they can tank this damage as well. While certainly they are very weak against immortals, it's far easier for the zerg player to make a quick transition to zerglings than it is for the protoss player to switch to colossi. Roaches fear sentries with force field. Because of their large display model, roaches get trapped and pushed very easily by force field. Burrow and tunneling claws are great for the regeneration they provide, since while storm doesn't kill them, it certainly takes a chunk out of them.
 
Hydra: While very strong against the protoss gateway army, they are very susceptible to colossi and storm. If your opponent is trending towards these tech trees instead of stargates or just pumping gateway units I'd say don't bother.
 
Ultras: What counters ultralisks? That's right, the zealot! A simple front line of zealots doom these guys, which protoss is going to have anyway to protect his stalkers/colossi from zerglings. I've tried so many times to make them work, and most of the time I can't justify them with their long build times and gas cost to see them lumber around and die without ever attacking.
 
Infestors: Neural parasite isn't worth it for colossi simply because roaches don't care about colossi, and stalkers don't really care either for the 8 seconds you have them controlled. Fungal growth does nothing as most fights happen at your base or his so there's no retreating anyway. If I believe 80 damage from storm isn't enough to cause concern for my troops, I'm pretty sure protoss isn't worried about 36 damage over 8 seconds on his troops.
 
Corruptors: I don't like these for combating colossi, because it's a lot of gas to put into a unit that's worthless after the colossi go down. With their short range and colossi having a LOT of stalker friends, corruptors are typically very expensive scourge. Only way, way slower. Sometimes it can't be helped and these are necessary. Generally when your opponent is sentry heavy or colossi count is 4+. A nice benefit to getting them for colossi removal is that you can make a pack of mutas for harassment since you need the spire.
 
The general plan against Protoss: I generally tend to want some mixture of zerglings, roaches, and corruptors. Queens will be my early defense against air. Since most people are teching to a robotics facility or templar archives, hydras tend to become obsolete very quickly as they die wholesale to storm and colossi. Tier 3 isn't very good against protoss, so the idea is to stay at lair. Your biggest issue will be colossi backed with sentries. In this case don't try and focus them down because it's generally not possible; get corruptors once you notice heavy sentries in the mix.
 
Zerg vs Protoss Replays
 
Here is how roach openings do against a 2-gate. Note: my micro and timings are a little sloppy here, but it gives the general idea.
 
 
 
Here is a very typical replay of me holding off a 4-gate:
 
 
 
Notice how him trying to retreat leads to immediate loss because of the resulting army compositions.
 
Zerg vs Terran
 
Your hardest matchup, by far. Any unit combination of theirs works against you, any opening of theirs works against you, and you can't crack their base for a long time. Creep is vitally important in this match-up, as there are many interactions which go in your favor on creep but against you off of creep.
 
The 13/13 build listed above is meant to force the terran away from certain strategies: namely a reaper and/or bio+bunker opening. Getting zergling speed with your first 100 gas goes a long way towards stopping reapers and hellions, and sets you up well for banelings too in case the terran goes bio (either walking to your base or by medivac). If they do these strategies anyway, great! You're fully prepared against those, and early cheese too. Now lets talk about the other 90% of openings.
 
The strength of terran openings isn't that each individual opening is hard to counter, it's that each opening requires a very specific zerg unit or upgrade to defend against it. Defend incorrectly, and the game immediately ends. Also, many openings transition into each other. Hellions lead very elegantly into banshees, or a banshee rush can backtrack into a hellion/marauder/thor push. And so on. A few examples: as soon as you have roaches to fend off the hellions, cloaked banshees are ravaging your mineral line. Or, after defending against the banshees, a tank is dropped off on the cliff overlooking your natural.
 
One note: the queens often have to help each other defend, so make sure to place a creep tumor down early to link your main and natural. Generally with your 2nd or 3rd 25 energy.
 
Reaper play: micro'ed properly, these units can eliminate infinite numbers of non-speed zerglings. With their huge damage to buildings, spine crawlers are actually a waste of resources. Builds that go for an early hatchery before gas have almost no answer to reapers, but we got gas first! Speed upgraded zerglings on creep dominate reapers and hold their own off of creep. Lucky for you, all your buildings and workers will be on creep! Spread overlords around your base so you know what direction they're coming from and greet them with zerglings. Make sure to keep up with zergling production if your opponent is massing reapers. Note: don't try to baneling bust against a terran going reapers. It's doomed to failure.
 
Bio/Medivac: Banelings and only banelings can bring down a bio-ball. I've tried mass zergling, roach, and hydra and none of them even remotely work. If you don't have banelings, you die. Simple as that. Do a surround with your zerglings/banelings; if you attack-move into the ball the terran can stim and run-attack-run-attack your force down. Generally the easiest strategy to beat, but remember to try and hit the marines with your banelings, not the marauders!
 
Hellion rush: A zerg base is wide open, allowing these fast jerks to scoot all over and wreak havoc. Place 2-3 spine crawlers at your natural and bring your queen at the main to the ramp to block. Generally just chase them away from your base or towards the spine crawlers; don't worry about hunting them down as you'll lose wholesale zerglings. On creep, zerglings win. Off creep it's more of a fair fight with hellions having a slight edge. Very difficult to stop on maps like Desert Oasis or Scrap Station because your queens can't help each other. The relatively good news is that hellions go obsolete somewhat once you get roaches or hydras. Also note that getting a surround is vitally important: hellions hit fewer targets when surrounded than when you are chasing it.
 
Thor rush: A thor drop into your main isn't that bad: zerglings can surround and quickly kill it while the queen deals with the medivac. A thor drop onto a cliff is a lot more difficult, as is a thor with some hellions/marauders in front of it. The best solution is to get roaches or hydras and focus it down (killing any repairing SCV's first).
 
Bio/tank push: Roaches, hydra, and muta get annihilated by bio/tank pushes. However, zergling/baneling do very well against it early and roach/baneling do OK against it later in the game.
 
Banshee: If you scout an early starport, it's not a bad idea to get a 3rd queen preemptively. However, putting down spore crawlers is probably going to be your best bet to avoid playing the "does he have cloak" game. The spore crawlers help to stop drops into your mineral line later as well.
 
Tank drop onto a cliff: There is no answer. Lost Temple, Kulas Ravine, Delta Quaddrant and Desert Oasis are all instant losses against a good terran if you expand early. The tank drop happens minutes before you have either mutas or drop tech. The "best" solution is not to build a second hatchery near a cliff, which is quite poor. If you think "muta" or "drop tech" will fix this, here's a replay of IdrA (vs Silver) spending his first 100 gas on ling speed, his second 100 gas on lair, upgrading drop tech soon after lair completes… and he's still MINUTES behind solving a simple siege tank on a cliff. Note: getting lair with the first 100 gas isn't an option as you'll die immediately to reapers and/or hellions. On these maps against terran, just do some sort of all-in attack: banelings or roach/ling.
 
Late game: Your 200 food army gets completely annihilated by his 200 food army, and it's not close. After defending in the middle-game you need to put the pressure on him somehow. Research drop tech or upgrade to Hive to try ultras and/or broodlords. Try and attack where his army isn't, because unless you out-food the terran by 40+ you're not going to win a battle against mech. Expanded creep greatly helps as your units close the distance quicker. Cover the map in purple as quickly as you can, and only engage on creep if you can help it.
 
A note only Planetary Fortresses: Attack them only as a last resort, and with a huge army (example: 20+ roaches). It's not uncommon to see a fortress with 30+ kills. Contaminate doesn't stop them from firing.
 
Key unit analysis in Zerg vs Terran
 
Queen: Oddly enough, this is often your best unit against a terran. It has 1 armor without being considered "armored" or "light", ground range 3 and air range 9 making it a strong defender. Add in transfuse, and this is one sturdy lady! There's no shame in having 4+ queens against a terran with only 2 hatcheries, even if it feels wrong. The only way the terran can punish you for having too many queens is with siege tanks.
 
Zergling: Absolutely fantastic all game, and even better later because they can become banelings too! Upgrading zergling speed is something you should do with your first 100 gas every single game against terran. Remember that you need a lot of these to be useful, and work on your surround technique.
 
Baneling: Crucial against bio play as a bio ball will melt everything else you have. It takes 5 banelings to break a depot, and 13 to break a barracks.
 
Roach: The more I play, the less I like roaches against terran. They get absolutely man-handled against bio (which they are supposed to be strong against), and only fare slightly better than zerglings against mech. Very expensive, especially supply-wise.
 
Hydra: Dies to marines, dies to marauders, dies to hellions, really dies to tanks. Dies to any terran unit when off of creep. Sadly, this is often the best option to survive the transition games that terran plays as the hydra attacks both ground and air.
 
Muta: Very good unit early, and relatively poor later. Muta harass is shut down hard by a 1-2 missile turrets, and mutas aren't very good in a fight. Still, they are very mobile and have their uses. I can't recommend having more than 8 since they perform so poorly in combat against anti-air units (marines/thors).
 
Broodlords and Corruptors: Vikings have a range of 9 and thors have a range of 10. Corruptors have a range of 6. It's ridiculous hard to keep broodlords alive against a terran.
 
Infestors: Useful to stop hellions/bio from moving, to uncloak banshees with fungal growth, and spawn infested terrans onto siege tanks. Not useful as a means to outright kill bio with fungal growth as the medivacs heal that right up no problem. Mediocre as if you have the infestation pit, you need to be saving gas for ultras.
 
Ultras: This is my tier 3 unit of choice as the only terran counter is 5+ siege tanks and/or thor 250mm cannons. Once you get these, make sure to control them separately from your zerglings as they tend to have very poor pathing AI.
 
The general plan against Terran: If I'm on some impossible map to expand, I'll do some sort of all-in with banelings. If they spot you and build a huge wall, whatever. Make a round of drones and get that 2nd gas ASAP so you can plow through more buildings. If the map is fine, the idea is to expand and rely solely on zerglings and queens for a long time. Build a spire, harass with about 6 mutas, and then take a 3rd and tech to hive. Zerglings and banelings are tasked with holding the ground against everything, which means you really have to keep up with your injections and creep spread. Your food count will look very low, and that's due to your army being 1 supply.
 
Replays ZvT
 
Baneling bust vs hellion rush:  
 
 
 
Baneling bust vs a fast expanding terran:  
 
 
 
Here's a game where my opponent has a brain fart and lets early zerglings into his base. He does recover and expand, but my macro is too great:  
 
 
 
This is a game that's a model to follow for what to do: expand early and hold off the attack. Expand again when you see your opponent has done so, and tech to hive. Go for ultraslisks to break his tank line. Put down a hydra den or spire to deal with any sudden air tech, and usually a spore crawler early on to prevent instant loss.  
 
 
 
Map Analysis
 
The worst maps for zerg are: Lost Temple, Kulas Ravine, Delta Quadrant, and Desert Oasis. On the first three maps, the natural expansion is tankable from cliffs. On Desert Oasis, your main is tankable from across the ridge. This forces you into one base play against terran, which generally means all-in styles.
 
The best maps for zerg are Metalopolis, Blistering Sands, Scrap Station, and Steppes of War. These maps allow for varied styles of play by both sides and don't strictly punish zerg for expanding early. The common theme between these maps is that there are wide open spaces and multiple angles to attack from, as well as not having tiny choke points to get slaughtered in.
 
Section 6: Tricks and tips
 
Zergling surrounds: don't just attack-move into the enemy. The zerglings bunch up and take forever to get to the target. Right-click past your target, and when the zerglings swarm around it you can either hit stop or attack-move to have them engage. This not only maximizes damage output for your army, it can be used to stop units from escaping. Very easy to do on creep because lings are blindingly fast.
 
Roaches vs non-charge Zealots: Roaches attack every 2 seconds and are slightly faster than zealots. Attack, move, attack, move, attack. Or similarly, you can attack, stop (press S), attack, stop. Pressing 's' will cause the roaches to attack anything in range, which happens to be the zealots. Very easy to do, very potent. Even better against zealots when on creep or with upgraded speed. Watch the 2-gate replay to see how this is done.
 
Overseers: I generally try and produce one overseer as soon as lair finishes. It allows me to scout my opponent's base now and then, and each time I contaminate a key building to delay big units or upgrades. Don't ever use changelings: everyone diamond/platinum level kills them immediately. The only problem with overseers is that for 50 extra minerals you can upgrade overlord speed, which is very useful and for all your overlords. I find contaminate better against protoss than terran because protoss will have very few stargates/robotics facilities and terran will generally have multiple factories/starports.
 
Roach micro: treat them more like zerglings and less like hydras. Don't attack move with them because they have a large display model and will all bunch up with only the front line attacking. Try to do a partial surround with them, and as soon as the opponent's front line dies move them up again in between shots. This insures that the roaches in the back are attacking too.
 
Roach burrow: The burrow-move mechanic of the roaches is fantastic in many fights. It's not always about the surprise factor; often it's the HP regeneration that makes it worth the research. It's 10HP per second gained, so it can be very advantageous to fight for a few seconds, burrow-move for 2 seconds, then pop out again. Most races won't care about detection vs zerg, so it's often a surprise to your opponent. Even being burrowed for only 2 seconds is a ton of HP gained throughout your army. One very relevant example is to reposition yourself when fighting colossi or tanks so you can snipe them. Protoss doesn't always bring an observer with them, and terrans will have to scan (which won't be instant). Not reliable for harassment as you can see the roaches moving underneath (WHY?), and most bases and expansions have a tower protecting them. You can also burrow-move under forcefields, but not under buildings.
 
Baneling drops: bring 1-2 empty overlords to go in front of the drop to take the cannon/turret hits. Try to approach from an angle where you won't be spotted until you're over the mineral line, so as to avoid having the enemy workers run away.
 
Creep tumors: Multiple creep tumors spread creep faster than one. This can allow you to catch up quickly if you were neglectful or needed injections, or repair damage that was done by the enemy.
 
Overlord creep and burrowed units: Opposing units can't build on creep or on top of burrowed units, so having overlords spew creep at expansion spots or a single zergling burrowed there can delay an expansion for some time. Overlord spew works amazingly well against a command center wanting to land on an island.
 
Wall-ins and ramp blocks: Always test to see if it's airtight before giving up (right-click move behind the wall-in/block). In a surprising amount of cases it's not airtight, allowing your zerlings to pour into his base and get a free win or free information.
 
Early exansion and drones: Even if you don't plan on making too many drones, split the drones evenly between your bases. This allows for more efficient mining and will allow you to keep up or even pass your opponent in mining rate even though you have equal or fewer workers! It also allows each base to take longer to mine out.
 
Spawning pool building and larvae: To have three larvae by the time your spawning pool completes, start saving larvae around the pool's 40% completed mark.