You guys voted for this post on Facebook. This post covers the basic scouting and key timing in TvP.

Disclaimer: This is not perfect, but just my personal rule of thumb.

Feel free to comment and share your scouting knowledge. Correct me if I’m wrong. If I mention a certain timing below, take it as an approximation. Let say, I said 5:00, it probably ranges from 4:45 to 5:15, as it is hard to precise if you take into account of other variables such as map size etc. Also, the main focus of this post is about scouting, so I won’t discuss about how to react.

Phase 1 – Basic Scv scout

This is based on the assumption that you play standard and scout at 14 or 15 supply.

Gateway

The first thing you need to look for is the Gateway. This is so elementary that this is not being mentioned most of the time. There should be one Gateway in the Protoss base now. If there isn’t one, there can be two main possibilities,

Nexus before Gateway

Proxy Gateway

The first one is straight forward.

The second one puts you on red alert. Build bunker(s) immediately. I won’t go in depth about how to hold one, because that exceeds the scope of this piece. Going back to scouting, after you have deduced that there is no Gateway and Nexus at Protoss’ base, you need to check the gas. If there is no gas taken, it is likely to be two Gateway Zealots. If there is a gas taken, it is likely to be one Gateway Zealots with Stalkers.

If there is a Gateway, look at the gas.

Assimilator

Let say it is a normal game, and you scout a standard Gateway timing. Look at the gas.

There should be at least one gas taken, the question is one or two. It is possible that no gas is taken for a 17 supply Gateway expand, which is a safe form of “Nexus first” in case of proxy Barracks. But it is rare.

One

It is likely that it is a standard one Gateway expand. When you scouted that there is only one Assimilator, you can choose to do an Engineering Bay block at the natural immediately (Flash’s favorite). Nowadays, Protoss usually start making a Zealot against an Engineering Bay block, and cancel it if there is not one. If you just scout around the base, the Scv should see the Nexus by the time it leaves the base.

This can be a quick Zealot + Stalker + Mothership aggression into expand. The first sign is that the Zealot is not cancelled after he sees that you do not do an Engineering Bay block. The second sign is Chronoboost on Gateway. The third sign is the Zealot walking across the map.

Another possibility is a four Gateway rush with one gas, and it is very rare.

Those mentioned above are based on the normal Gateway timing, but it can be a 10 supply Gateway Zealot + Stalker + Mothership aggression to counter Reaper opening.

Two

This is where things get more tricky. Many people suggest that two Assimilators mean that you need to prepare for Oracle. That is not completely true. After you see that there are two Assimilators, you need to count the number of Probes in each Assimilator. Further, the timing of the second Assimilator is a tell too, but that is too advance for me.

Four in total (two each)

This usually means Mothership Core expand. Subsequently, the 5th and 6th Probes will be placed back in gas to become a normal game.

You can tell whether Protoss is making a Mothership Core based on the animation on the Nexus.

Six in total (three each)

This usually means one of the following early tech on one base,

Proxy Stargate build is likely to have the second Pylon at the proxy location. So if you see two Pylons and two gas, it is unlikely to be proxy Stargate. If the proxy Stargate is being built with the third Pylon, the first Oracle cannot hit at 5:00. Clearly, if you scout the Twilight Council, it is either Blink or Dark Templar. However, it may be hard to tell whether Blink is being researched or not judging from the animation, and hence, a good sign is whether there is an abnormal number of Stalkers.

Outside of these three mainstream builds, Four Gate is a possibility but it is uncommon.

Phase 2 – Tech path

Phase 1 is mainly about whether Protoss is expanding or not. Phase two only occurs if Protoss chose to expand between the standard timing of 4:00 to 4:30.

Phase 2.1

After Protoss have expanded, they will have to choose their first tech path at 5:00. These include

Twilight Council

Robotic Facility

Stargate

5:00 is a key scouting time in TvP. Usually a Reaper is sacrificed at 5:00~5:15 to look for the tech building, and Terran will have to make use of this information to react accordingly. For Twilight Council, it is either Blink or Dark Templar. Again, the number of Stalkers is the key sign if you are unable to tell whether Blink is researching or you don’t see the Dark Shrine. If it is Blink, you have to know whether it is an all-in or a macro build (discuss this in phase 3). The Blink attack hits at around 8:00, while the Dark Templar hits before 8:00.

The timing of the Stargate can be earlier than 5:00 if Protoss cut the first Stalker, and the first Oracle should hit at around 6:30. The Robotic Facility build is perhaps not a big tell of what Protoss plan to do immediately as it has quite a number of options such as Colossus, Warp Prism and Immortal all-in. The Colossus build is perhaps the most normal of them all whereby Protoss camp in two bases for upgrades and Colossus. However, Colossus does not necessarily mean they are playing defensively as there is an all-in timing at around 10:00. Another interesting variation is the Colossus drop, and it hits at around 9:15. The Immortal all-in is less common, but it is still good to know that it hits at around 7:30. On top of these different Robotic Facility variation, the first Observer should reach Terran base at around 7:30, so keep an eye for a scan at that time.

Phase 2.2

Protoss usually go for one tech path at 5:00, and then another after that.

Let’s start with Stargate. The usual second tech after a Stargate tech is a Robotic Facility, and it will proceed to a normal game. This can shape up to a Colossus and Phoenix composition. Another less popular variation is the Twilight Council tech after Stargate for Zealot Templar.

The Twilight Council tech can be followed by a Dark Shrine after the Blink upgrade. The more common tech option is the Robotic Facility for Colossus, and this is perhaps the go-to build in the current meta. As I had discussed in the last post, Twilight Council into Robotic Facility is probably the best anti Widow Mine drop build.

Robotic Facility is usually followed by the Twilight Council path for Blink and Colossus, which is probably the standard build.

Phase 3 – All-in or macro

After you have scouted the tech path at 5:00, you are not sure if Protoss plan to do an all-in or macro. One way to tell is to check the gas at the natural at 7:00~7:15. If no gas is taken, it is likely to be all-in. You can watch any of the games I’ve linked above, and see for yourself. Whenever there is an all-in, the gas is not taken at the 7:00ish timing. Thus, it is normal for Terran to sacrifice the Reaper at 5:00 for the first piece of information, and scan at 7:00 for the second. The vod below shows INnoVation put down a scan at around 7:15.

Summary of key timings

Nexus at natural: 4:00~4:30

First tech: 5:00 (Stargate is at 4:30 if no Stalker)

All-in or macro: 7:00~7:15 gas at natural

One base Blink: 7:00

Proxy Oracle: 5:00

One base Dark Templar: 6:30

Two base Blink: 8:00

Two base Oracle: 6:30

Two base Dark Templar: 7:45

Two base Colossus drop: 9:15

Two base Colossus all-in: 10:00

Two base Immortal all-in: 7:30