Spire

From The StarCraft 2 Wiki

The Spire is a Zerg building important for making flying units such as Mutalisks.

Navigation - Protoss - Terran - Zerg [e]

Zerg Units (StarCraft II) [e]
(i) = Infested (z) = Zerg-evolution (g) = Swarm Guardian spawn
Ground Units:	Hive Queen | Larva | Drone | Zergling | Baneling (z) | Roach | Hydralisk | Lurker (z) | Nydus Worm | Infestor | Ultralisk
Air Units:	Overlord | Overseer (z) | Mutalisk | Swarm Guardian (z) | Corruptor |
Additional Units:	Broodling (g) | Infested Terran (i) | Infested Protoss (i) | Egg (z) | Lurker egg (z) | Cocoon (z)
Basic Buildings:	Hatchery | Extractor | Creep Tumor | Spawning Pool | Spine Crawler | Roach Den | Baneling Nest | Evolution Chamber | Spore Crawler
Advanced Buildings:	Lair | Hydralisk Den | Deep Warren | Spire | Nydus Network | Hive | Greater Spire | Infestor Pit | Ultralisk Cavern
Cancelled Units:	Shrieker (z)
Cancelled Buildings:	Sunken Colony | Spore Colony | Swarm Clutch

Zerg Units (StarCraft I & Brood War) [e]
(q) = Queen-infested (z) = Zerg-evolution
Ground Units:	Larva | Drone | Zergling | Hydralisk | Lurker | Defiler | Ultralisk
Air Units:	Overlord | Scourge | Mutalisk | Guardian | Devourer | Queen
Additional Units:	Broodling (q) | Infested Terran (q) | Egg (z) | Lurker egg (z) | Cocoon (z)
Basic Buildings:	Hatchery | Extractor | Evolution Chamber | Spawning Pool | Creep Colony | Spore Colony | Sunken Colony | Hydralisk Den
Advanced Buildings:	Lair | Hive | Spire | Greater Spire | Queen's Nest | Nydus Canal | Defiler Mound | Ultralisk Cavern | Infested Command Center (q)
Hero ground units:	Torrasque (ult) | Matriarch (qu) | Infested Kerrigan (it) | Unclean One (def) | Hunter Killer (hyd) | Devouring One (zlng) | Infested Duran (unk)
Hero air units:	Kukulza (mut, grd) | Yggdrasill (ovl)
(ult) = Ultralisk -- (qu) = Queen -- (it) = Infested Terran -- (def) = Defiler -- (hyd) = Hydralisk -- (zlng) = Zergling -- (unk) = Unknown -- (mut) = Mutalisk -- (grd) = Guardian -- (ovl) = Overlord