The Mantis Screamers that were assimilated and turned into the terrifying Mutalisks once built their towering nests on lifeless worlds, using any surfaces that could be found. The Spire, though similar in appearance to the Mantis aeries, has been altered to sustain itself by feeding on the Creep.

• Flyer Attacks. This evolution enhances the natural weaponry of the Mutalisk, Guardian and Queen.

• Flyer Carapace. This evolution enhances the natural defenses of all aerial minions of the Swarm.

The armored Greater Spire carries the genetic code for the deadliest Zerg flyers and cab be used to further enhance and evolve existing breeds. This stucture enbles the deadly Mutalisk to transform into its Guardian aspect, in which it sacrifices its speed and aerial assult to gain the ability to attack ground based enemies with devastating effect.