Requiring a Lair to build, this building contains access to all Flyer units and Upgrades listed below. The Spire is needed for the construction of the Zerg aerial units Mutalisk, a fast harasser and the Corruptor, an anti-air unit.

Once a Hive has finished, the Spire may be further upgraded to a Greater Spire for Broodlord end-game. Flyer Carapace gives all Spire units, which all have a large health bar and cost, will give the most effect right away but Broodlords also need Evolution Chamber's Ground Attack and Carapace upgrades for Broodlings and Ultralisk-tech switches to be more effective.