This week's StarCraft class didn't exactly go as planned. Students were supposed to give their final presentations today, but only one student who signed up for today was there to attend (the others preferred to fail the class apparently?).
The student that actually did present talked about strategy of containment in StarCraft. By his own admission, he is no top player, but did the best he could to understand when and how containment is useful and when it's not. He said he has about 150 APM and plays Protoss.
First, what does containment mean? It means trapping the enemy in his base, however you can. The student gave these advantages for using a containment strategy:
- Good for low APM players (like him). It usually doesn't take a whole lot of clicks to set up containment, but it can take a huge number to bust out of one.
- Takes advantage of superior flux. You set up your units just right (at choke points or in semi-circular formations) so that all your units will be able to attack at once while the enemy will probably not be able to accomplish that, given the terrain.
- Gives you map control. If the enemy is stuck in his base, you have free reign of the rest of the map so you can expand.
- Reduces the cone of uncertainty. If the enemy is stuck in his base, there's just fewer things he could possibly be doing.
- Reduces your scouting burden. Similar to the last point, scouting becomes less critical when the opponent is mostly stuck in one place.
- Stalemates help you. If you are containing the enemy, then there is a battle where both sides lose many units, even a statemate is acceptable to you. That's just more time going by where you can expand anywhere you want and the enemy cannot.
He listed these disadvantages to containment:
- You're vulnerable if the opponent does bust out. Your expansions might be spread out and poorly defended, especially if you spent a lot of time and resources keeping the containment going.
- You are maximizing the travel time to bring in reinforcements. If the opponent attacks your contain, he can get new units to the place of battle quickly, while your reinforcements probably have to travel from your base all the way to the enemy base.
- Containment is hard to setup in the first place as Protoss.
The student's original impetus for choosing this topic was that he often found himself being contained by other players, and he thought maybe he should be the one containing. But as a Protoss player, he said this strategy turns out to be not the greatest.
In Protoss vs. Zerg, the zerg player gets early control of the map, which makes setting up the contain difficult. And even if you do manage it, the Zerg has mutalisks which fly around quickly and ignore your containment attempts.
In Protoss vs. Protoss, the enemy player will probably reaver drop you if you try to contain. They might even reaver drop you anyway, which makes you look pretty silly for investing lots of resources in something that doesn't even affect what the enemy does. Another problem here is that if you do a contain, then the enemy tries a reaver drop, how easily can you defend against it? It's probably easier to defend if you spent some time and resources on defending...rather than parking units outside his base to attempt to contain.
In Protoss vs. Terran, vulture mines make it difficult to really maintain a contain and soon enough they will have siege tanks with siege mode, and then what are you going to do? Those tanks have the longest range in the game, so they'll bust out.
The student's opinion was that containment strategies are generally pretty good when you are playing as Terran or Zerg, but not as Protoss. Protoss units are so strong in the first place that having them standing around and not attacking is a waste, he said. The often-mocked "1, A, 2, A, 3, A" strategy (just attack with several packs of units) ends up being more effective with Protoss than contain, he said.
After his presentation, students played a few games of StarCraft as Professor Feng attempted to comment on the games in incredibly convoluted ways that would allow the spectators to understand what he meant without giving too much away to the players (they could also hear him). The best one was a Terran vs. Zerg game where the Zerg had an amazing start, taking out all mining at one of the Terran's two bases. The Terran player's iron will kept him in the game though and he was able to survive and survive and keep the Zerg player threatened enough that Zerg never really had time to get a lot of mining going at his several expansions. Eventually, Terran got his "ball of death" (tanks + goliaths mostly) together and rolled it over everything. This unstoppable force ended the game.
That's it for this week.