Though it existed only for a short time, its warriors were ferocious and deadly, and capable of infesting any creatures they encountered. Consisting of Hydralisks, Mutalisks, Ultralisks, Zerglings, Drones, Overlords, Queens, and later a unique strain referred to as "Roverlisks" (by General Duke), the Brood was assembled after the death of the Overmind by Kerrigan as one of the assault Broods of her new Swarm.
The Kukulkan Brood was formed on Char by Kerrigan after the death of the Overmind. The Brood remained there protecting the new Hive Cluster until a signal from am artifact on Bhekar Ro briefly threw the Zerg into chaos. She then ordered the Kukulkan Brood to locate the artifact and capture it.
The Brood used Behemoths, a massive strain of Zerg transport meant for carrying large numbers of Zerg through space, to travel to Bhekar Ro. The Swarm landed there and began infesting the world, building Hatcheries, Creep Colonies, and other structures so as to increase their numbers. In doing so, they infested "Old Blue", a sky-blue colored dog belonging to one of the colonists, and incorporated his genetics into a new strain of Zerg called the "Roverlisk". Endowed with traits including a heightened sense of smell, this was the Brood's only distinctive breed.
After the Protoss arrived, the Kukuklkan Brood began multiplying, producing more and more creatures including Guardians and Scourge, and fighting the Protoss. A huge melee ensued when the Terran Dominion under Edmund Duke also arrived. The Brood then began its offensive towards the town of Free Haven by sending waves of Zerglings, Hydralisks and Mutalisks though failed to break through the ever-standing colonists until they were just about to deploy a wave of Ultralisks, Alpha Squadron ground troops arrived just in time to the town and the Brood was driven out of the entire area.
The Brood then began its next offensive, this time on the Protoss who were guarding the artifact though also came into contact with a massive Alpha Squadron strike force as well as a commando squad and the Brood succeeded in driving out the former.
Eventually, the Xel'Naga artifact culminated into a new life form, and in its spectacular birth, the creature absorbed every creature and building of the Kukulkan Brood, as well as every Protoss soldier, destroying the Brood completely.
The Kikulkan Brood created and used the Roverlisk breed in combat.
Kukulkan was a feathered serpent god in Mayan mythology.