Devourers are an evolution of the mutalisk. In use by early 2500 during the Great War, devourers spit a venom of corrosive acid at aerial targets that can eat through the reinforced armor plating of terran and protoss capital ships. A single spit of venom may splash over multiple targets. The acid spores in the venom may hinder the fighting ability of the target.
Devourers were a regular sight among the zerg's aerial and stellar forces well into 2512. Under the reign of OverqueenZagara, Devourers were often modified to transport and launch objects other than corrosive acid.