Forum: gaming.stackexchange.com
Tags: <starcraft-2><starcraft-zerg>
Title: Why do Zerg players build their Evolution Chambers quickly?
Question: I often see Zerg players build spawning pool immediately followed by an Evolution Chamber (EC).  What is a purpose of that quick EC? To get quick armor/attack upgrades for zerglings?  Sometimes I also see a Zerg build EC without building extractor... so how he is going to get gas in this case?

Answers:
sents: text: There are two reasons for the quick Evolution Chamber.
text: Reason One
text: The first, as you noted, was early upgrades which can quickly turn a fragile force (take zerglings for example) into an early game force to fear.
text: However without gas this isn't a feasible strategy.
text: If attempting this build order, gas first is a must to make use of that early Evolution Chamber.
text: Reason Two
text: What you are witnessing is preventative measures designed to protect against early air pressure.
text: With Banshees, Void rays, and Mutalisk a consistent threat, a Zerg can unlock the ability to build spore crawlers providing both detection and vital air defense.
text: The extra protection is often worth the extra resource cost to help the Zerg survive to mid-late game where they can overwhelm their opponent with macro.
answer_details: author: gaming.stackexchange.com/users/6431/Aardvark
score: 28
sents: text: Yes, to increase the effectiveness of early Zergling/Speedling harassments, early upgrades are good.
text: In the case that you see an Evolution Chamber without an Extractor, he unlocks the Spore Crawler .
answer_details: author: gaming.stackexchange.com/users/998/Tamara Wijsman
score: 3
sents: text: I'd say it is a quick and cheap way to free up some supply, for a building you'll need eventually anyway.
text: Might also be used for wall-ins/sim city.
answer_details: author: gaming.stackexchange.com/users/4378/Per Alexandersson
score: 3
sents: text: I don't agree with any of answers doesn't handle case of EC necessity in EARLY game (is build together with Spawning Pool w/o gas).
text: Gas is absent, so you won't be able to start upgrades; Opponent Air Units will be absent yet 2 or more minutes, so there are no value from ability to build spore colonies
text: My guess, why they build EC very early is they are just supply blocked and want to release 1 supply.
text: It is not too reasonable though, as they can build extractor (it is only 25 minerals)...
answer_details: author: gaming.stackexchange.com/users/3467/Budda
score: 2
sents: text: It can be effective.
text: It DOES make a person who scouts you not think about putting out early air.
text: Its a decent fooling tactic.
text: Additionally, if you are capped out, have no larvae, and have huge mineral surplus.
text: You need that building later on, but will you have the time/money/drone when you have to produce a consistent stream of army units?
text: Do you neglect to build a roach warren if the other person is getting something that can counter roaches?
text: Even if you tech up, maybe they build something later that completely destroys you because you didn't have a roach warren built and couldn't produce them in time.
text: And because you didn't build the building before you needed it, but only after.
answer_details: author: gaming.stackexchange.com/users/None/
score: 2
sents: text: Getting an evolution chamber early is usually a mistake.
text: Unless the zerg player took two extractors early, they won't be able to make the upgrades, and air/cloaked units will take a while longer.
text: It's better to put those minerals into getting an expo up.
text: I usually don't get an evolution chamber until I have my expo ~50% saturated, and by then I can get an overseer scout to see if there's any air production.
text: The exception is if you're able to scout a VR, banshee, or DT rush, because those can occasionally come before lair tech.
text: Personally I have experimented with a build that gets early +1 speedlings to defend the expo and deny scouting and fast expands.
text: But of course that requires gas.
answer_details: author: gaming.stackexchange.com/users/11378/Kirro
score: 2
sents: text: Maybe he had a defensive tactic in mind.
text: When evolution chambers die, they spawn broodlings.
text: Broodlings aren't as a secure a defense as spinecrawlers are, but they may be a decisive factor when defending a base since they attack, and they may give the player some time to return to his base to defend.
text: Tt gives sporecrawlers and upgrades, if the Zerg needs some.
answer_details: author: gaming.stackexchange.com/users/13081/Guilford
score: 0
sents: text: Tonight I learned that carapace before speed is really really really good vs marine pressure openings.... slow lings with +1 armor do way better vs marines then speedlings without any armor.
text: They actually do better vs marines then +1 attack speedlings, if the marines don't try to run away etc....
text: The issue is there speed and the difficulty in getting surrounds with out speedlings....
text: but your going to get speed shortly after anyways.
text: Here's another weird tip that sounds like it can't work
text: but it does.
text: +1 carapace with lings is better then +1 attack vs unupgraded stalkers as well.
text: BUT +1 attack is way way better vs stalkers if they get the armour upgrade.
text: I'll leave it to you as an excercise to figure out why.
text: I would go as far as to say that evo chamber at the same time as your pool hard counters marine + tank openings and pure bio openings.
text: (NON-reaper)
answer_details: author: gaming.stackexchange.com/users/47658/furyOfSkanks
score: 0

Summary of the answers:
Early upgrades are good, it increases the effectiveness of Zergling/Speedling harassments. It is a quick and cheap way to free up some supply.
It is generally agreed that it increases effectiveness of early harassments, and is a cheap and quick way to free up some supply. It also be some kind of defensive tactic. Some do say however that doing so is a mistake.