Zerg versus Terran: Everything I know

This is the style I am most comfortable with because it does really well when you have good positioning. On top of that, it hinges on upgrades and a faster hive which is exactly what I like to have. And the upgrades that you are getting really improve the Ultralisk/Baneling style that I use in the lategame.

This Infestor-ling style excels at defending pushes, where Mutalisk-Baneling will have a lot harder time at defending such as the Marine-Tank push. But it cannot delay or put aggression on the Terran well because the Infestor is so pivotal in defending. Aggressive Terrans or Terrans which play revolves around the big midgame push will have a lot more difficulty dealing with this style, but macro Terrans that take a quicker but safe third base will have a slightly easier time. Fortunately, not a lot of Terrans take a third quickly AND safely that they aren't punishable.

This style also has a relatively short midgame, because you are relying on the stronger beefier hivetech units to put back pressure on the Terran rather than your Infestors and Zerglings.

Requirements



You need quick upgrades with this style, because you are heavily reliant on Zerglings. Which both benefit heavily on the upgrades but also need to outupgrade the Terran units to be cost-effective in engagements.

Personally, I start my +1 melee before I start my Lair. When the Lair finishes I get another evolution chamber and get +2 melee and +1 carapace with them. These upgrades are crucial, because they will augment your Hive tech on both fronts and as you tech to hive fast you need the upgrades fast. On top of that, the Zerglings you are relying on in the midgame will be more cost-effective against pushes and drops.

You can also not take a third before your macro hatchery. You need to be able to make a snap reinforcement of a lot of Zerglings in case there is a random push coming up, and a third will often be near the Terran forces and can be more easily harassed than an inbase macro hatchery. On top of that, if you havexcess energy on your main queen, you can tap that to use it on both hatcheries before you have to build another queen to spawn larvae.

You should also get your Infestor tech up as fast as possible. This means getting the Infestation pit the second your Lair finishes , and building the Infestors once the pathogen gland upgrade moves past the 30 second mark while its being researched. After your pathogen glands finish, you should aim for the neural parasite upgrade right after. This combination will make dealing with Marine-Tank midgame pushes a lot easier.

Delaying

The whole point of this style is that you can get a Hive out slightly before the 15 minute mark. Because of that, you obviously want something that can delay or dismantle a variety of pushes. Both of this fits the Infestors glove perfectly.

Your Zerglings should always be out on the map, in the least outside of your natural with some scouting Zerglings on key scouting positions in the line of attack. These Zerglings can be used to force a siege on the tanks simply by feigning a big attack on the Marine-Tank ball. The best way of doing this is by moving in from two sides at once. This gives the Terran a feeling that you are committing to a huge flanking manoeuvre and thus incentive to siege up. If the Terran has to leap frog their tanks all the way over the map, the push will be delayed by a ton.



If Marines are leading the push, a single fungal growth will deal so much damage that the Terran will have to turn around or lose a lot of them that are supposed to tank the Zerglings. And a fungal on a little group of Siege tanks and Marines will snap them into place for a little while, giving you little amounts of time that will give your reinforcing army more time to safely spawn.

Positioning and punishing bad positions

Infestors with their range are one of the few Zerg units that rely on good positioning other than spreading them out or attacking in a concave. If there are Infestors out on the map, the Terran cannot move their Marines forward very far at all. They have to stay by the Siege tanks and preferably behind them. Sieged up tanks have a range of 13 and the fungal growth spell has 9 range, 10 range if you count the radius too. This gives the Infestor a 3 range lee-way of moving around and casting their spell.

If you catch a Marine ball with your fungal growth, you should time the next fungal growth out to be slightly less than 4 ingame seconds. This way you won't give the Terran time to retreat the Marines out of the grip. If you have killed a large amount of Marines with a couple of fungals, move in with all of your Zerglings and wait until you are atleast near the last Siege tank before you Attack move. This will make it so your surround will be much better and will make the Zerglings not focus on the 'meatshield' in the form of Marines. In the engagement, grab the first couple Siege tanks with neural parasite while keeping the other Infestors ready for a clutch fungal growth. This should give you a cost-effective engagement if you did it correctly.



If you can't catch a large amount of Marines before the engagement, there is another way to start to engage your Terran opponent. Move a couple of spreaded out Zerglings towards the entrenchment while keeping your Infestors on stand-by. As soon as the Tanks show up into view, cast a couple of neural parasites on the frontal ones. As your Infestors waggle forward, move your huge Zergling force in before the Tanks can shell at the Infestors to draw fire away from them. Then as the Infestors latch onto the Tanks, move the rest of the Infestors in and start blanket fungalling the Marines while your Zerglings attack them. The Marines should die a very quick horrible death due to the massive splash damage all around, which gives your Zerglings all the room to surround the Tanks and easily take them out.



A great position to have your Infestors before an engagement is on the high ground. In case the force wanders along this ledge, this will give you the perfect place to start neural parasiting and fungalling the units without the Terran knowing. If there is a medivac around, this plan will obviously not be as effective. But you can easily retreat down to the lowground once you spot a Medivac. Also don't just do one single neural parasite, the Terran will notice and instantly scan the high ground where the Infestors will quickly die to tank fire of the other tanks the Terran has with his push.