INnoVation has been opting for a 13 gas opening in his recent TvT games, and it has garnered some attention for the right reasons. This post is to discuss the train of thoughts behind this build, and how this works in comparison to gas first openings.
This is an example of the 13 gas build that INnoVation has been doing.
Background
13 gas is very old, but it may seem new to newer players because it has not been used for a long time. 13 gas in TvT is arguably the most common opening back in the early days of Wings of Liberty, whereby you mainly go for cloak Banshee (there were other 13 gas builds, but Banshee was the more dominant one). One of the many reasons why 13 gas has “died off” was the rise of gas first openings in general. This was mainly due to the fact that gas first can do what 13 gas did at that point of time, but better. Given that the Starport is down earlier for gas first than for 13 gas, the 13 gas player cannot go for a Banshee to match opponent’s Banshee due to the offender versus defender rule of thumb. While the 13 gas player can opt for a Raven to counter the gas first Banshee, there were other better and more popular builds at that point of time. I won’t go further here because there were many other factors, so in short, gas first replaced 13 gas for a period of time.
The reason I compare 13 gas with gas first and not other openings is mainly down to how similar the way the resources line up for both openings if you go 1-1-1 double gas.
13 gas advantages
Despite its relative shortcoming in the Banshee metagame at that time, 13 gas has some advantages over gas first. First, you put down the Barracks earlier, and hence, you are less vulnerable to proxy Barracks cheeses. Pretty straightforward. Second, the later Refineries allow you to put down the Command Centre quicker than gas first in general. Again, this is pretty basic. However, it is the implications of these two points that make it superior for a defensive game plan in the modern metagame.
Defensive openings
The common mech openings nowadays are usually defensive openings. By defensive, I don’t mean you turtle, as you can still be aggressive with your Hellions and so on. The key is again the offender versus defender concept (I can’t help myself but to link it again because it’s that important in TvT) at the beginning stage of the game, and mech players generally want to get an early Raven, which put them in the defender role. Many times in interviews, Terran players like Flash will emphasize on how important Raven is in TvT. Raven is particularly important for mech. Thus, if you look at the recent mech openings, they usually involve getting an early Raven. Therefore, when you combine the importance of Raven and the general tendency to be defensive, the conclusion will lead you to move from gas first Raven to 13 gas Raven opening.
I have come across countless comments on various forums (for example) that recommend other Terran players to go for gas first Raven opening as it is safe against [almost] everything. Rather than debating the statement itself, I want to argue that 13 gas Raven does better than gas first Raven if you want to be safe. The two key reasons are mentioned above in the last section. While the first reason of having an earlier Barracks has been used to justify why 13 gas is safer than gas first, the second reason of having an earlier Command Centre has been explored less (at least not explicitly). Simply by delaying the first Refinery by one or two supply in the opening stage allows you to get an earlier Command Centre to make a difference. Since your game plan is to be defensive, you want to be ahead by having a relatively early Command Centre. Yes, the difference in the timing is minor (no more than 0:30), but there is no reason not to have it earlier if you can. In fact, to reinforce this point, I dug up a vod with Bomber opening up with 14 gas Raven last year (I deserve a cookie for remembering this).
Bomber delayed the Refinery by another supply and took it at 14 in order to squeeze out an even earlier Command Centre. Of course, this also means that the Raven is delayed slightly, but the timing of it is in time to match a gas first cloak Banshee. As you can see in the above vod, the Raven is out at around 6:40, which is earlier than a gas first cloak research timing of 6:45.
Comparison with other mainstream mech openings
Even though I emphasize on the advantage of 13 gas being able to get an earlier Command Centre than gas first for Raven opening, other mainstream mech openings actually get an even earlier Command Centre. Going back to the first vod I linked above, Flash was using the gas first Reaper opening, while INnoVation was using the 13 gas, so it provides the perfect comparison in terms of how the two popular mech openings line up. The Command Centre was down earlier for the gas first Reaper opening, but Flash has to invest in Engineering Bay and Turrets because the build doesn’t get a Raven out in time to match the standard cloak Banshee timing. It is really hard to argue which is better as it can be down to preference and metagame, since they are reasonable trade-offs.
Personally, I prefer 13 gas as it gives me the flexibility to switch from being the defender to the offender according to opponent’s opening. In the vod below, MMA was going for a standard 12/12 Reaper opening, while INnoVation was using the 13 gas opening. After scouting MMA’s opening, INnoVation knew that he had the initiative in deciding who was the offender and the defender because his 13 gas opening will put down the Starport first. Thus, in response, he decided to go for cloak Banshee instead of Raven, because MMA could not possibly have an earlier Banshee than INnoVation with a 12/12 Reaper opening.
Other considerations
Some may argue that the third advantage of 13 gas Raven over gas first Raven is the “ability to Scv scout”. This is based on the assumption that gas first opening does not or cannot go for a standard Scv scout, and it is something that I do not agree on completely. This debate is clearly beyond the scope of this post, so I won’t go too much into it. I may discuss this in the future.
I want to end this post by making something clear. I am not claiming that 13 gas Raven is out right better than gas first Raven. The fundamental ground that my above arguments base on is that you want to be safe and have a defensive game plan. In other words, gas first Raven can be better if you want to be offensive after the various standard 6:30 to 7:30 aggression timings. The gas first Raven allows you be decently safe for that time period, and provides a good counter attack potential. For example, you can go for an auto turret Tank drop, or Viking Tank push.