15 gas opening is the oldest and arguably the most common opening in TvT. I have been trying to find the best way to react against Banshee opening, and here it is.
15 gas build is perhaps the most middle of the road build in TvT. It can shape up to a timing (see the basic build order below) or react to opponent’s build accordingly. This opening can also move towards a bio or mech composition easily.
Basic build order
10 – Supply Depot
12 – Barracks
15 – Refinery
16 – Marine and Orbital Command
17 – Supply Depot
Produce 2 Marines and build a Reactor
@400 mineral – Command Centre (@100% – Orbital)
@100 gas – Factory
@100% Reactor – 4x Marines (2 production cycle)
24 – Supply Depot (Build Supply Depot accordingly hereafter)
@100% Factory – Starport. Swap Factory on Reactor. Produce 2x Marines from Barracks (2 production cycle) and 6x Hellions (3 production cycle)
@100% Starport – Medivac
Move out with 8 Marines, 6 Hellions and 1 Medivac
I did a more detailed write up a year ago.
Reaction against Banshee
The build order above is very tight on mineral, and does not have the adequate defense against a Banshee. Therefore, something has to be cut in order to get the right defense. Flash did a textbook reaction against Bbyong in the SanDisk Shoutcraft (Game 3 and Game 5).
10 – Supply Depot
12 – Barracks
15 – Refinery
16 – Marine and Orbital Command
17 – Supply Depot
Produce 2 Marines and build a Reactor
@400 mineral – Command Centre (@100% – Orbital)
@100 gas – Factory
@100% Reactor – 4x Marines (2 production cycle)
24 – Supply Depot (Build Supply Depot accordingly hereafter)
Everything up till here remains the same. You still get Hellions and Starport.
@100% Factory – Starport. Swap Factory on Reactor and produce Hellions
However, cut Marine production. The resources will be spent on an Engineering Bay.
@125 mineral (while Starport is building) – Engineering Bay
@100% Starport – Viking
@100% Engineering Bay – Missile Turrets
The Missile Turrets will complete just when the Banshees reach your base. The first Viking will start to zone the Banshee if it gets in range of the Missile Turret detection vision.
TerranCraft 
Very nice tutorial. The only thing I would like to add is the ebay timing.
You need to start it at 06:00 to build the 3 turrets in time.
I also highly prefer to go 12/12 2 reapers or 14 gas 1 marine 1 reaper as it saves me the scan to scout.
I think the best follow up is to build a TL with the barracks after the initial marines and to straight build a tank after 4-6 helions. If you time that perfectly you have a tank at 09:00 which helps immensely against those 1 base tank pushes.
I asked Liquid Bunny on twitch chat why he goes no raven against banshee opening and he said that you have to delay it in favour for the 09:00 tank which you need against 1 base pushes.
My understanding is that if you’re doing mech, constant Hellion production for map control. The Hellions can clear up the 1 base push if you know it’s coming. But yes, if you’re going bio, it’s standard to swap the tech lab and produce Tanks.
Pretty interesting on the Raven logic. I’ve not thought of that.
Oh yeah when your going mech it’s a different story xD.
15 gas is just an opener and there are still a lot of decisions you have to make later on to survive into midgame.
I’ve been using Bunny’s 15 gas for bio (ravenless with tank) and Streloks 15 gas for mech.
The strelok build is very interesting. He goes for second gas at 4:40 and gets a second factory very early. This allows him to get that 09:00 tank while also being able to produce a raven. Most mech players go 15 gas into 3OC and just then start adding the second and third factory.
But I’m nitpicking here ;). Your article covers all the main points
No worries, you did bring up relevant points. Based on the recent comments, I notice that I’m too into “standard builds” and not so much about the unorthodox ones. I certainly never heard of the quick second factory. Paste me link on vod!
Here you http://www.twitch.tv/navistrelok/b/513928600.
Just watch the first game on stream on Frost.
Game 3. Imo made me not want to use that opener at all.
Even though Byong does not do damage with the banshees, and takes his natural way later than Flash, he ends up winning a lot of the battles. He is always the agressor, he has map control, he outmaneuvers Flash. I’m actually stealing Byong’s opener :)
Please feel free to also take a look at HTOMario and his analysis as well his play (e.g. https://www.youtube.com/watch?v=YdOBf6OooGc) as a multiple random GM preferring Terran.
Maru has developed his own build (Maru’s anti banshee expand) to counter banshee and other agressions come after @6:15 if there weren’t banshee there. Maru’s build provides better active for the defender vs. banshee and other agressions without making turrets and prepare for any agression if the oponents do not go for banshees. The build goes for 2 tech paths. First, if banshees were there, raven and 2 viking will be made to chase the banshees down. On the contrary if they go for autoturret tank drop, we can tech switch our buidling techlab to factory to produce siegetank and a naked starport to make 1 or 2 vikings to slow down tank push or spot medivacs. Though noone plays HOTS now , but i think it may be helpful in the future. Your thread is very good as always. Keep it up! I appreciate it !
I forgot to say that the opening of Maru’s is similar to the one above. 15 gas opening
I think I had seen it before, but I couldn’t remember much of it. Surprised that you are able to dig up this old article.
I still playing HOTS ladder, sometimes i fossick your threads to expect somethings interesting to improve my games, also for entertainment. :v
Haha, I hope my articles are entertaining.