"Apparently, many of the renegade Cerebrates, commanded by Daggoth, have merged into a new Overmind. Fortunately, the creature is still in its infant stages. It can't control the Swarm yet, but Daggoth and the others still have control over most of the Broods."
The Second Zerg Overmind, also known as the new Overmind, the fledgling Overmind or simply the Overmind was the 'leader' of Daggoth's Renegade Swarm. It was created by several cerebrates merging on Char.
The death of the first Overmind caused a schism in the Swarm, with Sarah Kerrigan and Daggoth each coming to control half of it. Daggoth ordered many cerebrates to merge on Char to create a new Overmind. This was partly motivated by the realization that the cerebrates were not designed to exist without an Overmind. The nesting site was located near the Khalis crystal. In its infancy the new Overmind could not exert control over the entire Swarm, and the cerebrates remained the primary nexus of control. Kerrigan plotted to destroy it and ensure her independence.
Recovery of the Khalis
The protoss attacked the Overmind's nesting ground while recovering the Khalis. The attackers were accompanied by Kerrigan who took control of some of the local zerg to assist. The protoss recovered the crystal and withdrew without killing the Overmind.
"Once you deliver neurostims to a fledgling overmind, everything else is a piece of cake. Trust me."
The invasion of the Koprulu sector by the United Earth DirectorateExpeditionary Force heralded further travails. In their bid to dominate the sector the UED sought to take control of the Overmind and, through it, the Swarm. The activation of the psi disrupter disrupted zerg cohesion and left the Overmind vulnerable to attack. The invaders subdued the Overmind with powerful neurostim drugs and powerful psychics. This effort was publicly known as Project "Black Flag". The number of zerg the UED managed to conscript remained limited and Kerrigan later suspected the UED's control of the Overmind was imperfect.
Struggle for Control
"My Queen, we have located a small Terran facility towards the rear of the Renegades' landing zone. There appears to be a number of UED scientists working within the compound, but we are unable to determine the purpose of their presence..."
"I know what they're up to. I suspected that the UED's control of the Overmind was tenuous. Tarsonis is too remote for them to maintain direct control over the Swarms, so they've sent these 'scientists' to coordinate their attack."
The Overmind's enslavement by the UED allowed Kerrigan to secure an alliance with Commander Jim Raynor, Fenix and Emperor Arcturus Mengsk, against the UED. Indirectly this would work toward her ultimate goal of destroying the Overmind and assuming control of the Swarm. The UED plan began to unravel when the unlikely allies destroyed the psi disrupter, allowing Kerrigan to more effectively compete for control with the Overmind.
With the UED's power waning after the liberation of Korhal, the UED launched an attack on Kerrigan's base of operations on Tarsonis. Here the difficulties the UED was having controlling the Overmind and the zerg was apparent. Tarsonis was too distant for the UED to control its zerg remotely and they were forced to dispatch "scientists" to coordinate the attacks on-site. The elimination of the scientists caused the UED to lose control of their zerg on Tarsonis.
Slaying the Beast
"Zeratul, my faithful servant. You must aid Kerrigan in this endeavor. The Overmind is our common enemy. It must be destroyed to insure that our people will survive!" "You ask me to aid this vile creature?" "I do not ask this for myself. Nor do I ask it on Kerrigan's behalf. I ask you to do this for our people, Zeratul. Obey me as you always have...Trust in my judgement."
Kerrigan knew that to destroy the Overmind she needed the Dark Templar. She assured Dark PrelateZeratul's assistance by kidnapping MatriarchRaszagal. Kerrigan and the Dark Templar attacked the UED and Overmind on Char together. Zeratul personally slew the Overmind. Kerrigan then eliminated the remaining opposing cerebrates and assumed control over the entire Swarm.
Effect on the Swarm
"Once again I stand atop the broken bodies of my enemies. Victorious but not unscarred. The Earth-borne Directorate has been destroyed. And the Overmind lies dead and trampled beneath the ashes of Char."
The death of the Overmind and Kerrigan's ascension altered the Swarm's structure. The remaining cerebrates did not survive long as they were never intended to exist without an Overmind. Kerrigan effectively replaced the Overmind as a new supreme nexus but had no need for subordinate cerebrates.
The Second Overmind appears three times in StarCraft: Brood War; once in each campaign. In "Return to Char," it can be "destroyed" (damaged to the point of sending it into remission) as an alternative to extracting the Khalis crystal. In "To Chain the Beast," it is an invincible structure; one need only move medics onto the beacons surrounding it to win the mission. In "To Slay the Beast," destroying the Overmind is compulsory. Unlike "Return to Char," only dark templar can destroy the creature.
↑Kerrigan: "Look, I don't need to tell you all what might happen if that thing reaches maturity. I can guarantee you that should it awaken, it'll take full control of me just like it did before. I don't want that to happen, and I'm pretty sure you don't want it to happen either." StarCraft: Brood War. Vivendi Games. Level/area: The Quest for Uraj (in English). 1998.
↑Underwood, Peter, Chris Metzen and Bill Roper. StarCraft: Brood War (Manual). Irvine, Calif.: Blizzard Entertainment, 1998.
↑Samir Duran: "My Queen, we have located a small Terran facility towards the rear of the Renegades' landing zone. There appears to be a number of UED scientists working within the compound, but we are unable to determine the purpose of their presence..." Kerrigan: "I know what they're up to. I suspected that the UED's control of the Overmind was tenuous. Tarsonis is too remote for them to maintain direct control over the Swarms, so they've sent these 'scientists' to coordinate their attack." Duran: "Cerebrate, focus your attacks against the Terran facility. All of the UED scientists must be killed. Only then will we be able to finish off these Renegade Zerg." StarCraft: Brood War. Vivendi Games. Level/area: Fury of the Swarm (in English). 1998.
↑Zeratul: "Kerrigan, this is Zeratul. I demand to know why you've taken our Matriarch." Kerrigan: "Actually, Zeratul, she's not the one I'm truly interested in. I stole her to get to you. You see, I need you and your brethren to kill the Overmind for me. The only way I had of assuring your cooperation was to take away that which you value most. However, I give you my word that once you've killed the Overmind, I'll allow her to return to you." Zeratul: "As if your word held any value..." Raszagal: "Zeratul, my faithful servant. You must aid Kerrigan in this endeavor. The Overmind is our common enemy. It must be destroyed to insure that our people will survive!" Zeratul: "You ask me to aid this vile creature?" Raszagal: "I do not ask this for myself. Nor do I ask it on Kerrigan's behalf. I ask you to do this for our people, Zeratul. Obey me as you always have... Trust in my judgement." Zeratul: "Very well, Matriarch. The Overmind will die this day." StarCraft: Brood War. Vivendi Games. Level/area: To Slay the Beast (in English). 1998.