Overlord

"Overlords provide control for your minions. As your forces grow in number, you must hatch more Overlords to control them."

- Daggoth

The overlord is a zerg flyer that provides control for lesser minions.

Overview
Overlords were evolved from the Gargantis proximae, a species of giant space-faring and semi-intelligent creatures which volunteered to be assimilated to avoid extinction. Once assimilated they were used to help cerebrates control and coordinate their broods and scout using their enhanced senses.

Overlords with the correct growth stimuli could carry other zerg within hollows in their hides. In this form they became deep-space transports ; the importance of their function was underlined by the sheer number of overlords found accompanying zerg forces.

The overlord's cerebral structure was complex with neural pathways woven throughout the body; this made it a powerful psionic energy transmitter. To preserve this capability, the zerg only altered neurologically impotent parts, including the carapace and pulmonary chambers. As a result, the overlord's core genetic matrix was atypically homogenous: over 90%. The minimal alterations also preserved memories ; ancient overlords, essentially assimilated Gargantis, regained their individuality upon becoming feral. Overlords used helium-filled gas sacs and a weak telekinetic psi-ability for lift and motive power. Their exoskeletons were strong enough to resist a lightning strike. Unlike most other zerg breeds, overlords had a greater capacity to act on their own judgement; their mental flexibility was still severely limited. Overlords typically only relayed orders. They were technically capable of directly controlling lesser zerg, but only with extreme difficulty.

Overlords were fairly docile. Additional duties included tending to young larvae and monitoring the progress of drones through a type of instinctive telepathy. By the Second Great War, overlords could disgorge creep to prepare the way for zerg conquests, and were used to metamorphosize into overseers. Overseers featured enhanced senses and could spawn changelings.

After Kerrigan's defeat at Char, some overlords attempted to form pockets of organized zerg in the same manner as broodmothers. However, this was a token effort, and most zerg regressed to a feral state.

StarCraft
The overlord is a versatile zerg flier that provides control, detection and air transportation once upgraded. It is slower than other transport units even with Pneumatized Carapace.

Development
During StarCraft alpha development, overlords had an attack value of 4.

StarCraft: Ghost
Overlords make an appearance in StarCraft: Ghost. Some have been locked into tanks or subjected to cybernetic surgery. The latter are known as brain spectres.

StarCraft II
In StarCraft II, the overlord provides control but does not provide detection. The overlord may evolve into the overseer which is a detector and spellcaster. Against protoss, it is recommended to keep overlords surrounded with strong anti-air defense as they are highly vulnerable targets for phoenixes used in the harass role.

The reason for the changes and the split between the overlord and overseer in terms of detection was that the zerg "were somewhat 'detectorific'" in StarCraft.

Heart of the Swarm
A special overlord skin is unlocked via leveling in Heart of the Swarm.

When Kerrigan reaches a certain level overlords provide more control and are spawned instantly. This ability is called Improved Overlords'.

Development
They regained the ability to transport units as of December 2008. Overlords used to have a slime ability, but that has been removed from the latest build.


 * Slime (also known as "Corrupt Minerals")
 * The overlord could drop a non-attacking slime creature, temporarily disabling resource nodes and xel'naga towers. The minerals can be covered as they're being harvested, enabling raids which slow down an enemy's economy. The creature must be killed before the minerals can be accessed.
 * This ability took some time to "cast" and had a small cooldown timer.

Variant Strains

 * Brain spectre
 * Mastermind Overlord
 * Yggdrasill

Evolution

 * Overseer

Individuals

 * "Green Eyes"
 * "Purple Eyes"