TvZ: Early Roach Ravager Attack

Early Roach Ravager attack builds are very popular in the TvZ match up now. There are two different builds that attack with Roach and Ravagers early on, and I will discuss how they are different. More importantly, how to play against them.

Two different builds

When I read about discussion people have about the “Roach Ravager build”, I notice that some are referring to different builds without realising it. We are currently at the post 2-1-1 dominant metagame whereby there is a wide range of builds used for both sides, and both of the Roach Ravager builds I discuss in this post are used now. One is more economical as it transitions to a macro game, while the other is arguably an all-in.

All-in version

14 – Spawning Pool
14 – Extractor
14 – Extractor
16 – Roach Warren

or

12 – Spawning Pool
14 – Extractor
14 – Extractor
14 – Roach Warren

Clearly, the latter is more extreme, but the general idea is the same. However, in my opinion, the 12 Pool 14 Roach Warren is stronger, because it hits that bit earlier to make a difference in whether Terran need to cancel the Command Centre (I will discuss this later). This is an all-in, as Zerg have to break Terran’s defence by continuously rallying units, and Zerg don’t have a second Hatchery. As you can see from the vods below, once Zerg realise they cannot break Terran, they just concede. The goal is to win with the build.

The timing hits at 2:45~2:55.

Economic version

16 – Extractor
16 – Spawning Pool
18 – Hatchery
20 – Roach Warren

The first vod below is an example between ByuN and Dark from IEM Gyeonggi last year. I brought this vod up to show that this build was not designed specifically against Reaper Reactor Hellion opening that some say it is, Dark used this against ByuN when 2-1-1 was still the most popular TvZ build. The other two vods are used in this season’s GSL recently. The goal is to get a lead in the early game.

The timing hits at 3:20~3:30.

Identifying the builds

I don’t recommend skipping on worker scout in the current metagame, and a normal Scv scout at 17 or 18 supply should be the norm. On a two player map, the Scv should be able to tell whether it is a Hatchery first build, and both Roach Ravager build variations do not go for a Hatchery first. The economic version is a Spawning Pool before Hatchery opening, so the Scv should see the delayed Hatchery. With that being said, it is possible that Zerg do not build the Hatchery at the natural (see aLive vs. Scarlett above). The all-in version simply does not have a Hatchery. Another way to figure out which variation it is is to look at the number of gas geysers taken.

The timing of the Scv scout should align with the completion of the Reaper, such that the Scv should have gathered the necessary information mentioned above for you to decide whether to put down a Reactor after the Reaper. It is common to put down a Reactor after a Reaper opening (for both 15 and 16 gas variations), even though you can get a second Reaper (depend on the specific opening) or a Marine before putting down a Reactor. This has important implications on how to defend against these two Roach Ravager builds.

Defending against them

All-in version

The goal is to survive, as it is an all-in.

The timing of the attack is at around 2:45~2:55, and that is very awkward to any one Barracks expand opening. This is because your Command Centre on the low ground should finish in the same time frame, then whether Zerg manage to make it in time to kill the building Scv to force a cancel makes a big difference. It is really hard to make the call, as it depends on map distance, and how many seconds your Reaper can buy when the Ravagers are moving across the map. I will use the first game between TY and soO in GSL quarterfinals as an example (vod already linked above), it is cross spawn on Whirlwind, and TY used a 16/16 Reaper expand. Whirlwind cross spawn is probably the farthest you can have for travel distance in today’s map pool, and a 16/16 Reaper opening’s Command Centre is that few seconds earlier than a 15/16 variation. Taken together, if it is possible for Terran to have the Command Centre completed in time against this build, these conditions are as good as they get. However, the harassment from the two Zerglings delayed the Command Centre a little, and TY decided to cancel it in the end. Something similar happened in game 4, even though the distance is shorter and the Zergling harassment was slightly less effective.

The question then is whether the Command Centre would have completed in time if the Zerglings did not create any delay. If you look at the game between Leenock and Keen, the Command Centre completed just in time, and that was under the condition that the Zerglings did not manage to delay the Command Centre. Given the fact that the map distance is closer than the two other examples, it appears that Zergling’s ability to delay the Command Centre has the strongest influence on whether the Command Centre gets to complete or not among all the factors. In other words, when your Scv scouts that it is not a Hatchery first build, you should leave your Reaper behind to defend against the two Zerglings. However, another factor to keep in mind is that Leenock used 14 Pool 16 Roach Warren while soO used 12 Pool 14 Roach Warren, so it seems fair to conclude that 12/14 is the stronger version solely based on this (I didn’t do any specific test to compare the two closely).

Going back to the Scv scout and Reactor discussion, when you scouted opponent is doing this build, you should not put down a Reactor. This is because you are not producing any Marine while the Reactor is constructing, and the Reactor is likely to only make one round of Marines. Thus, it is as good as making two Marines with a naked Barracks since the Reactor will get taken down quickly. Then, it is not justified to make a Reactor in this situation.

I like Keen’s approach towards this build, he lifted his Barracks away from the ramp in order to build a Bunker on the same spot. The Bunker right on top of the ramp basically prevented the Ravagers from getting onto the high ground. There should only be three to four Ravagers when the attack first hit, and it takes more than four Corrosive Bile shots to take down a Bunker. Thus, as long as you manage to repair the Bunker, you are quite safe. While Zerg wait for more Ravagers to “one-shot” the Bunker, Terran are also buying time to get a Siege Tank. Once Terran have a Siege Tank, the attack is more or less held. Of course, you make sure you position the Tank in such a way that it is in range of the Ravagers when it can attack the Bunker, but the Tank is out of range from Corrosive Bile at the same time.

On the other hand, TY’s approach focuses on the use of Cyclone, and hence, it is going to be a battle of micro. Pulling Scvs to repair the Cyclone and dodging Corrosive Bile shots during battle are paramount to the success of the defence. In my opinion, Keen’s approach is cleaner, and it is doable at any level. Even if you want to use Cyclone instead of Tank, I still think lifting the Barracks away for a Bunker on the ramp is crucial.

Key points

  • Cancel the Command Centre if there is any delay by Zergling.
    • If it can complete, lift it back into the main.
  • Do not build a Reactor. Lift the Barracks and land it farther away from the ramp. Constant Marine production.
  • Build a Bunker where the Barracks was at the top of the ramp.
  • Get Scvs to repair the buildings (prioritise Bunker over Supply Depot).
  • Rebuild Supply Depots if those at the ramp are about to get destroyed.
  • Buy time for Cyclones or a Siege Tank.

Economic version

The goal is not to get a bad trade, while you try to stabilise.

The timing hits at a time when your Command Centre is upgrading to an Orbital Command, so you don’t have to worry about having your Command Centre cancelled. The next thing is whether to build a Reactor after a Reaper. Since the timing hits later, the Reactor may be better than just constantly making Marines, as you can benefit from the boosted production. However, I think the position of the Reactor based on the angle of the ramp may play a part in the decision, and the Reactor will be taken down easily by the Ravagers if it is part of the wall.

For the convenience of the discussion, let’s take it that the Reactor is built and it is not part of the wall. You build a Bunker near the ramp (watch ByuN versus DRGLing) for the same reasons. Again, you need Scvs to repair the Bunker to buy time. Subsequently, you can get a Tank out and stabilise.

I think Siege Tank is better than Cyclone in this situation. Terran will have enough time to get a Tank out when the attack commence, and it is easier to secure the natural with Tank. The key difference between this and the all-in version is that, you don’t just want to survive, you want to start mining at the natural as soon as possible. Another reason for favoring Tank is that it allows a stronger follow up push against a Roach Ravager composition, and the push can consist of Marine, Tank, and Banshee.

Key point

  • Build a Bunker near the main ramp.
  • Lift Command Centre back into the main.
  • Get Scvs to repair the buildings (prioritise Bunker over Supply Depot).
  • Rebuild Supply Depots if those at the ramp are about to get destroyed.
  • Buy time for a Siege Tank.
  • Secure the natural as soon as possible.
Advertisements

2 thoughts on “TvZ: Early Roach Ravager Attack

  1. Thanks for this topic.

    Another game with the all-in version.
    It took place at the Nation WARS IV Elazer vs Innovation, Innovation starts with double medivac drop build. Let’s see how he defends. :)
    I still use this build. so i need to be able to defend it. Here factory comes later on because of the 2 rax.
    I think the key points are:
    -Bunker
    -Stim + marauder
    -Stop SCV production
    -Lift second CC on high ground,
    -SCV pull when needed,
    -Rebuild supply depot
    -Start factory when possible.

    What do you think about it?
    Also, Innovation put bunker on low ground, does it worth it ?

    1. Oh, I actually forgot about this game. I think the best way to defend is to build bunkers on top ramp and repair, and get more bunkers when you can afford. The goal is still to buy time for a Tank. Concussive shells maybe a better choice than stim in this situation. Elazer could have executed it better, and he perhaps should not try to destroy the CC (it is an all-in). He gave INnoVation time to gather a bigger force to hold the high ground.

      I would have just build a bunker on the high ground instead. A low ground bunker is a lot weaker than a high ground one, because the Ravagers have to rely on corrosive bile only (and it’s hard to destroy bunker with repair as I mention in the article). If Ravagers try to attack the attack the bunker by walking up the ramp, it is hard to form a concave to shoot at the bunker at the same time. The Ravager at the front will die before that even happen. Also, when the bunker fall at low ground, it is almost certain that the bio it will die.

      INnoVation also did not get a Factory even though he can afford to, so that is a mistake on his end.

What do you think?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s