This build is focused on high numbers of upgraded mutalisks as well as zerglings and banelines for support. Burrowed banelings increases the efficiency of the banelings to save gas for mutalisks.
15 - Hatchery
17 - Extractor
16 - Spawning pool
20 - Zergling x2
21 - Queen x2
25 - Zergling speed
Pull two drones off gas
30 - Queen
32 - Spine crawler
35 - Evolution chamber
35 - Hatchery
Put drones back on gas
37 - +1 Ground carapace
40 - Extractor x3
42 - Lair
44 - Baneling nest
44 - Spine crawler
50 - Spire
50 - Centrifugal hooks
50 - Burrow
60 - Flyer carapace +1
60 - Mutalisks x10 (or more)
70 - Flyer attack +1
70 - Spire
You want to continue to upgrade your mutalisks as well as taking additional bases. Spend your excess minerals on drones, spine crawlers and zerglings. Use your mutalisk flock to harass your opponent in as many places as possible: the mineral line, their production and stray buildings. Transition into broodlords to take advantage of your air upgrades and use infestors to support.
