"It is believed that the semi-intelligent spacefaring leviathans known as the Gargantis Proximae were first inducted into the Swarm so that their heightened senses could benefit the Zerg in battle. Whatever their starting point, Overlords were rapidly evolved to relay commands and keep the Swarm coordinated during combat. The importance of this function is underlined by the sheer number of Overlords found accompanying Zerg forces. Overlords are extremely flexible in their support role, often serving as advanced scouts and disgorging creep to prepare the way for further Zerg conquests. With the correct growth stimuli, Overlords are even capable of evolving the ability to transport Zerg warriors within their hollow carapaces."