12 Pool (vs. Zerg)
12 Pool is a very safe opening in ZvZ that gives you a lot of versatility. Nowadays (2016-2017) the build seems to be especially trendy in the Korean scene precisely because of this reason. It gives protection from most early Zergling rushes from a faster pool while also giving a superior economy. Even though its safeness comes at a cost versus 12 Hatch, which has a much better economy, it is not at all insurmountable since you also have 2 bases at your disposal.
- 9 - Overlord
- 12 - Spawning Pool
- 12 - Extractor
- 11 - Expansion at natural
- 10 - Produce Zerglings Check Build
- Metabolic Boost @100 gas (see note)
- Lair when your economy allows it (see note)
- Spire @100% Lair (see note)
Build Order Clarification
Scouting is key in ZvZ. It is extremely important to identify your opponent's opening as soon as possible since different openings require widely different responses. Whenever you have vision of your opponent's Hatcheries, you should be looking at what is hatching from his/her eggs. If you see your opponent making a lot of Zerglings, you want to make a lot of Zerglings as well. If you see him/her making Drones, you want to make Drones. If you are at a Larvae disadvantage however (i.e. have later or less Hatcheries), it will often be necessary to put down a sunken colony at your natural to secure it. This can delay your spire. The basic rule is to copy your opponent for 99% while trying to squeeze in a drone the other 1% of the time (Especially valid if your opponent and you opened with the same build order).
Finally, you want to know the Spire timing of your opponent. If his spire is a lot earlier than yours you might need to use Spore Colonies to defend until you can get your Mutalisks out.
Typically you will take one Drone off gas after you've mined the first 100 for Metabolic Boost. This is necessary because 12 Pool with a second Hatchery is really tight on minerals. If you keep 3 Drones on gas, you will not have enough minerals by the time you get your next 100 gas to start your Lair immediately, unless you decide to save Larvae/skip Zerglings.
Your Lair should start around 3 minutes into the game if you took one Drone off gas. Versus a very aggressive 9 Pool you will need to pull 2 Drones to help defend. This means you can be mining gas with only a single Drone or not at all. After the threat has passed it is up to you to decide your Lair timing. In some cases it can be better to focus first on minerals for Drones and Spores, and then tech to Lair and get your Spire.
If you have build nothing but Zerglings all game, you will be very tight on minerals. If you want to build your Spire as soon as Lair completes, you will have idle Larvae. Remember to start saving minerals slightly before your Lair finishes if that is your goal.
- 4-7 Pool (see Notes)
- 4-7 Pool (see Notes)
- 12 Hatch
4-7 Pool can be counted as a hard counter on 2-or 3-player maps, where the players' Overlords will provide enough information to decide where the opponent is located.
On 4-player maps this becomes harder as the player needs to rely on luck in scouting or where he sends his Zerglings.
vs 9 Pool (speed first)
You will need to pull 2 Drones to defend your natural together with your initial 6 Zerglings. This is even more so the case if your opponent is located in close-spawn positions (for example on Fighting Spirit). You will know your opponent went speed first in case his Zerglings gain speed roughly 15 seconds before your natural Hatchery finishes.
You can engage his Zerglings before your own speed finishes but it can backfire in case you lose the fight. Your main goals should be:
- Do not let your natural Hatchery fall.
- Don't let any Zerglings get into your main.
- Don't lose your 2 defending Drones
However, any Zerglings losses your opponent takes that are not reciprocated or equal are very beneficial for you as you will have 2 times his number of Larvae. If the opponent loses too many Zerglings (meaning the opponent won't have enough to efficiently guard his own ramp), you can be very aggressive and try to force 1 or even 2 Sunkens. In case the opponent gets greedy, you might even be able to end the game right there.
In case neither of you have suffered any significant Zergling losses early on and the opponent goes to guard his ramp you have two choices:
1. Try to break his ramp
You want to reduce his Zergling numbers as they can be a big problem for you. If the opponent has many Zerglings left over the opponent will easily be able to take his natural expansion while putting on pressure on your mineral lines with his Mutalisks. Don't go all-out though as it can backfire rapidly ending in his Zerglings taking out your Spores when you have no ground forces left.
By reducing his Zerglings number hopefully you will be able to delay his expansion while also forcing his Mutalisks to stay at home, defending it. Meanwhile you should have gotten your Spores and should be droning up trying to get a gas advantage.
2. Drone up
Your other option is to rapidly start droning and try to get a big gas advantage that the opponent won't be able to catch up to. However, this means your opponent will be able to take his expansion uncontested. Since your Lair is most likely delayed and you are not forcing his Mutalisks to stay at home by being aggressive, you will definitely need Spores. Try to take advantage of this fact during later stages of the game in case his Mutalisks are out of position.
In case the opponent's not expanding, be wary of the opponent Sunken pushing your natural during the time you are relying solely on Spores and Zerglings.
vs 9 Pool (Lair first)
As discussed in the previous section, you will need 2 Drones to help defend. In case you get a lucky scout and see the opponent's going Lair first, you can decide to not pull the 2 Drones as the opponent will not gain speed significantly before you, or even at all (in case the opponent skips it completely). Pay close attention to your natural Hatchery's timing. Roughly 15 seconds before it finishes, his speed should finish. If it doesn't, you can immediately start taking map control.
Behind this you again have 2 options:
1. Try to break his ramp
In case the opponent's being greedy and his Zergling count is low, this is very effective and you might be able to end the game by going all-out. Else it's better not to try to break it as his Mutalisks hit much earlier than if the opponent went speed first and you will cripple your economy too much.
2. Drone up
If the opponent's not being overly greedy, it's better to Drone up and solidify your economy. It is however a good idea to get a large number of Zerglings to force his Mutalisks to stay at home to defend his natural. In case the opponent slips up, you can easily delay it by forcing a cancel, which will be very good for you. In case there's no expansion coming and the opponent has a large number of Zerglings, you should be wary of the opponent Sunken pushing your natural.
If you can delay his expansion even somewhat while taking minimal Drone losses, you should be able to get a gas advantage that will be very difficult for the opponent to overcome.
See sections about 9 Pool. The only difference is that Overpool will have everything slightly delayed compared to the 9 Pool variant. With solid micro, you can most likely get away with pulling only 1 Drone, or no Drones at all, in case of speed first.
vs 12 Pool (regular, 2nd hatch @natural)
If your opponent opened with the same build order as you, it is a good idea to mirror what s/he's doing while trying to get away with one or two extra Drones. In a situation like this, the person who gets their Overlords to his opponent's bases first has a big advantage of exactly knowing what they are building.
By getting those few extra Drones you can hopefully take your 2nd geyser earlier and will have a Mutalisk/Scourge advantage. Building the 2nd Extractor and getting enough Drones to saturate it however is very costly (both on minerals and Larvae), you will most likely need to build Scourge to keep using your gas. Therefore, watch out in case your opponent is showing no sign of taking his 2nd Extractor as s/he can get an overwhelming amount of Mutalisks that way before your gas advantage starts kicking in.
vs 12 Hatch
In case you scout your opponent on first try, before you make your initial 6 Zerglings, you can make 2 extra Drones after placing your natural Hatchery. This allows you to put a 3rd Drone back on gas immediately. You will need to build a Sunken at your natural as soon as possible though or you risk getting overrun by Zerglings. Since your speed finishes considerably before your opponents, you can use your Zerglings to pin the opponent down in his base for the time being. As soon s/he gets speed you should be very careful.
Your next goal should be to mirror your opponent while remembering the golden rule of squeezing in a Drone when you can. From hereon the situation should play out very much like a 12 Pool vs 12 Pool as your Lair timings are essentially identical.
In case you don't scout your opponent on first try, you should try to pin him/her down with the Zerglings you have. Behind this you get 2 Drones, one to put on gas and one to build a Sunken at your natural. This is assuming your opponent is building only Zerglings. If the opponent's getting Drones or a Sunken, react accordingly by getting a few more Drones yourself (behind your own Sunken).
vs 9/10 Hatch
12 Pool has an advantage against a 9/10 Hatch but it is not as big as if you were 12 Hatch-ing. Your economy is stronger, you have earlier speed and an earlier Lair (that is if your opponent even decides to keep mining gas). The economy of a 9/10 Hatch build is essentially so poor that it won't be able to afford to keep more than maybe a single Drone on gas. In case your opponent is not mining gas, and is building only Zerglings, it is important to also keep making Zerglings. You should invest in a Sunken at your natural and if you feel unsafe you can even get 2. The only thing your opponent will be able to do is Zergling all-in you so don't skimp on defenses. Your Mutalisks are on the way, which will force the opponent to build Spores s/he can not afford. As always it will be important to monitor your opponent's Larvae usage. Your opponent might try to suddenly switch into a lot of Drones. Even then, it will be very difficult for him/her to catch up to you regardless of whether you decide to make Drones as well or Zerglings. Pressuring your opponent with Zerglings can further delay his/her Spire, while droning as well will allow you to saturate your 2nd geyser much sooner.
There's only 2 ways a 9/10 Hatch will have a reasonable chance and that is:
- By surprising you with mass Zerglings if you played too greedily (not getting a Sunken, too many Drones) or
- In case your opponent scouts you on first try and responds appropriately. If this happens, your opponent will be able to make 2 Drones immediately instead of Zerglings and still be completely safe against any pressure you can put up. To catch up in Lair timing your opponent could even delay or skip Metabolic Boost and research Lair instead. Even after all these steps, your economy is still slightly stronger than his. If the opponent doesn't get Metabolic Boost you will be free to get a few extra Drones and saturate your 2nd geyser before your opponent. If the opponent does get Metabolic boost, it will finish ~10 seconds later than yours if the opponent researched it before his Lair. If the opponent went Lair first, it will finish ~10 seconds after your Lair is complete. It either case it will be important for you to put up "fake pressure" and squeeze in a Drone or two to strengthen your economy. If the opponent went speed first, you should be able to take out one of his Overlords with your advantage in Spire timing. If the opponent went Lair first, you should take advantage of his lack of map control to strengthen your economy even more. Be careful however as a 9/10 Hatch does have a significant larvae advantage over you and a sudden switch into mass Zerglings can still take you by surprise if you do not pay attention.
This build is not particularly strong on any map, but it is more commonly seen on 3-player maps that have a wide choke.
This build is weak on any map that has a short travel distance between main bases.
- Ride of Valkyries
Soulkey opens up with 12 Pool versus hero's 12 Hatch. Soulkey delayed his Pool by about 5 seconds, made only 4 instead of 6 Zerglings and kept his 3rd Drone on gas longer so he could tech to Lair sooner. So it's not a 100% standard 12 Pool.
Larva opened with 12 Pool vs ZerO's 9 Pool (who went Lair first).