Since the previous post on the double Medivac Stim timing build in TvZ, the build has now become one of the most popular builds in the match up. In this post, I will discuss some of the details that I did not discuss in part 1.
14 – Supply Depot
16 – Barracks
16 – Refinery
@100% Barracks – Reaper and Orbital Command
@400 mineral – Command Centre (@100% – Orbital Command)
@150 mineral – Barracks
@100% Reaper – Marine*
@100 mineral – Supply Depot
@75 mineral – Refinery
@100% Marine – Reactor
@100 gas – Factory
@100% Barracks – Tech Lab (@100% Stim)
@100% Factory – Reactor and Starport
Constant Marine production and build Supply Depot accordingly hereafter
@100% Starport – Swap it onto the Reactor of the Factory and produce 2x Medivac
When you can afford, build 2x Engineering Bay.
I will explain the asterisk later.
This build has been used by many professional players in every region, but I will only use the vods from the recent SSL and GSL qualifiers for discussion because of the availability.
Build order details
The asterisk above is mainly down to whether a Marine or a Reactor is built after the Reaper has completed. A Marine is usually produced after a Reaper for this match up, because it helps to fend off the Overlord scout. However, recently for this build, some players have chosen not to produce that Marine and get the Reactor immediately. I was wondering if that affects number of the units loaded up into Medivacs, but it appears that they are more comparable than I thought.
ByuN used this build against Rogue in SSL qualifier for both the home and away map (above vods), and he made a Marine in one game but not the other.
After looking at the vods closely, the Factory and the second Refinery sequence is quite flexible. In the upper vod (set 2), ByuN went for Supply Depot-Marine-Reactor-Factory-Refinery. While in the lower vod (set 17), he went for Reactor-Supply Depot-Refinery-Factory. I scrutinised other vods just to ensure that the sequence difference is down to the opening variation of getting a Marine or not. Interestingly, ByuN actually had a different sequence in his game against Impact (vod below) when he made a Marine. The sequence is Marine-Supply-Depot-Refinery-Reactor-Factory.
Since I was still not convinced with the differences yet, I further compared them with INnoVation’s games against Dark in GSL qualifier (vods below). In both games, INnoVation did not get a Marine, and the sequence is Reactor-Supply Depot-Refinery-Factory. Therefore, I conclude that ByuN may be a little bit off in his set 17 game against Rogue, and the standard sequence is as follow.
With Marine: Marine-Supply Depot-Refinery-Reactor-Factory
Without Marine: Reactor-Supply Depot-Refinery-Factory
To put it simply, it is always Supply Depot-Refinery-Factory, and the Reactor fits in according to the variation.
The most important question is, does the opening variation affect the units loaded into the Medivac later and the timing of it?
Based on the vods, the variation doesn’t seem to affect these two things, even though there are minor differences in these five games. The key is that you should be able to load up both Medivacs with sixteen Marines and move out before 4:45. It appears that INnoVation simply has better mechanics than ByuN and he can have his Medivacs out by 4:30, which is earlier than ByuN’s by around five seconds. As for the number of Marines, both players leave a Marine or two at various places, and hence, the number of Marines in the Medivacs varies by one or two. Realistically, you can move out at around 4:40 with sixteen Marines.
It seems to me that the first attack location is flexible, and it depends on the convenience of the spawn location. Interestingly, neither ByuN nor INnoVation dropped in the main directly, and INnoVation always went to the third Hatchery first. It is rather hard to evaluate ByuN’s choices, because they were obviously affected by the spawn locations and opponent’s build.
Nevertheless, the key is not to drop in sight of Zerg, because you want to unload everything before stim-ing in. Subsequently, you have to make decisions on the fly to pick units off and move around the bases accordingly.
Follow up details
This build has a set up of two Command Centres and 2-1-1. In order to move to the next convergent point (3-1-1 on three bases), you need to build a third Command Centre, a third Barracks and two Engineering Bay. Based on the games I have watched (not just the five vods in this post), this is the part where almost everyone just has his/her own preference on which to build first. This also shows the logic of convergent point, whereby you can do whatever you want as long as you converge back to the key check points.
With that being said, in my opinion, I think the best sequence is 2x Engineering Bay-third Command Centre-third Barracks. This is due to the fact that the build took two Refineries early on in order to construct the tech buildings, two Medivacs and Stim upgrade, but the gas is not well spent right after that. All the additional structures required for the next convergent point do not use gas, and hence, it is likely that you will bank up gas and starve on mineral during the process. It is not ideal to pull workers out of the Refineries temporarily, because you are already mechanically stretched with the two Medivacs of units. Therefore, I think it is better to put down the Engineering Bays before other structures in order to spend the gas on upgrades. The reason to have the third Command Centre before the third Barracks is essentially down to the common understanding that you don’t want to have 3-1-1 on two bases unless you plan to have a two base timing, and that does not align that well with this build.
Another way to spend the gas is to get more Starport units, like Medivacs and Liberators. Intuitively, it sounds nice to make another pair of Medivacs to keep up the pressure and drop at multiple places. However, the resource doesn’t allow you to have another two Medivacs of units quickly, as it takes multiple production cycles from the Barracks to have that many Marines. Even if you produce Widow Mine from the Factory, the timing and resource don’t line up well. This resource limitation is also evident when both ByuN and INnoVation have only one additional Medivac to follow up. Thus, Liberator is a better option if you want to spend the gas on units and not upgrades.
There is a habit for Terran players to place the Factory next to the first Barracks, because it allows them to swap add-on quicker. This is a staple when Reactor Hellions are the bread and butter of the match up. Since the Factory does not require to swap add-on with the Barracks, it can be placed away from Zerg’s plausible scout vision in order to hide as much information as possible. The same reasoning applies to the second Barracks.