Hatchery:
This town hall produces all the Zerg units. It's very useful since they only cost 300 minerals as well. The Zerg need about 3 hatcheries now per base, since the larvae respawn so slow. You can't really hide these structures since they create creep all around.
Extractor:
The start of the Zerg's main production begins with gas. This is more important than anything, since mutalisks, hydralisks, queens, guardians, and upgrades rely on this heavily.
Spawning Pool:
This is your first structure that really means something. It allows for zerglings, sunken colonies, and the lair. If you lose this, you most likely lost
Creep Colony:
Makes the purple creep crap
Sunken Colony:
This structure got a major upgrade since the last patch. With a nice attack rate, they chop up Marines like nothing now, as with everything else. They make good anti-reaver drops, since they have 400 HP to absorb a few scarabs.
Evolution Chamber:
This is a must if you plan to use hydralisks. Building two isn't such a bad idea, making those precious upgrades finish faster. It's also needed for spore colonies which have some uses.
Spore Colony:
This is good detector when overlords aren't around. Good fire rate, and now they do normal damage, they can stop mutalisks now.
Hydralisk Den:
Hence name, it does the Mutalisk thing
Lair:
After this is completed you should go directly with your plan and construct or upgrade something since that's why you made this in the first place. A lot of options are now available once this structure is complete..... keep that in mind.
Spire:
One of the most important structures that the Zerg must keep alive. This provides for the production of mutalisks and scourges, two units you'll use often...........
Queen's Nest:
The name's it. (Queen Upgrades)
Hive:
Now all upgrades can be made to 3/3..... other than that the rest of the advanced structures are available.
Greater Spire:
Well its definately bigger than your old spire, I don't think it's greater. Now try not to lose this structure since you spent a lot of time and resources on it. Besides that you get access to guardians and devourers.
Defiler Mound:
Defilers are deadly if used correctly, actually they're deadly if used at all. Building two of these to get the upgrades faster wouldn't be so bad.
Nydus Canal:
This is a must on island maps. Otherwise you can try to cut down the distance your hydralisks have to travel by using these. Also it's great to surprise someone who doensn't know that you plan to canal into his base.
Ultralisk Cavern:
Well this lets you produce ultralisks.
