Swarm host evolution is an evolution mission available in StarCraft II: Heart of the Swarm.


The world of Cruxas III, a colony for the Terran Dominion, was under seige by broodmother Kilysa. The Dominion was employing nuclear missiles to slow her advance. Abathur located a nest of carrion wasps near the city of New Babylon and suggested assimilating their essence would allow mutations to the swarm host breed. A force of swarm hosts destroy the nest and mutated into the carrion strain, producing flying locusts. The new carrions proceeded to destroy the Dominion's nuclear silos, allowing the zerg invasion to continue unhindered.

On the planet Ignus, the broodmother of Ignus Brood had been killed by the Dominion, who were advancing on the brood's hive cluster. A member of the local fauna, an ash worm, was also attacking the brood. Abathur determined the ash worm's tunneling abilities could be of use in mutating the swarm host and gave the suggestion to destroy it and assimilate its essence. The swarm hosts successfully killed the ash worm and assimilated its tunneling skills, mutating into the creeper strain. The creepers used their new abilities to defend two outlying hive clusters from Dominion strike teams, securing the remnants of the brood.[1]

Gameplay and WalkthroughEdit

In the first part of the mission, the player will command a number of swarm hosts to destroy a small number of Dominion forces and the carrion nest beyond them. When the swarm hosts mutate into the carrion strain, the player can use the flying locusts to attack the nuclear silos across pits. The second silo has ground defenses along the path including a siege tank, so the swarm hosts should burrow well away to avoid fire.

In the second part of the mission, the player receives control of more swarm hosts and must destroy the ash worm. It will burrow and move away when taking enough damage but is easily hunted down. After mutating into the creeper strain, the player must use the creeper's Deep Tunnel ability to bring it to the outlying hive clusters that appear and defend them. Sunken colonies will aid in defense and work to draw fire from the creepers. When both Dominion teams are dead the mission is won.


In earlier builds of the mission, the carrion swarm hosts would have destroyed terran blockades that prevent groups of banelings from destroying the nuclear silos.[2]


  1. Blizzard Entertainment. StarCraft II: Heart of the Swarm. (Activision Blizzard). PC. Mission: Heart of the Swarm, Swarm host evolution (in English). 2013-03-12.
  2. Blizzard Entertainment. StarCraft II: Heart of the Swarm Map Editor. (Activision Blizzard) (in English). March 12, 2013