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: