StarCraft Episode II

StarCraft Episode 2 is part of the StarCraft storyline -- the history of the Zerg in the fictional universe of StarCraft. StarCraft is a real-time strategy computer game released by Blizzard Entertainment in 1998.

Introduction
The StarCraft science fiction universe features three races: the renegade human Terrans, the noble cybernetic warrior Protoss, and the horrific bug-like Zerg. The storyline covers the fortunes of these three races and their leaders, fighting for dominance in a remote region of the galaxy.

StarCraft Episode II features the Zerg campaign after the attack on Tarsonis.

A Great Prize
The Zerg have crushed the Terran forces on nine of the thirteen main Terran worlds, including Tarsonis.

After the defeat of the Protoss over Tarsonis, Tassadar's forces and the Zerg fought over the core continent of the planet. However, the Protoss withdrew from the surface as they could not keep fending off the Zerg.

The only opposition left to the Zerg on Tarsonis were Omega Squadron, which had been so weakened it posed little threat.

Meanwhile the Zerg had acquired a chrysalis containing something very important. The Zerg which had performed the capture had belonged to the Jormungand Brood, but the Zerg Overmind created a new Cerebrate to control a new brood, whose sole purpose was to protect the chrysalis. The new Cerebrate was informed that the Overmind could reincarnate it if it "died".

Its first priority was defeating the remnants of Omega Squadron in order to prevent them from destroying the chrysalis. The Squadron was located by Zasz, another Cerebrate. The Zerg were successful. The Overmind was pleased, and said that as long as its charge remained intact, it would remain pleased. Thus, its life and that of the Cerebrate guarding it would be made as one.

Egression
The Overmind decided to travel to Char in order to keep the chrysalis safe, but doing so required the Zerg to clear a space platform over Tarsonis of the remnants of Tassadar's forces. With help from Cerebrate Daggoth of the Tiamat Brood and his Hunter Killers (specialized Hydralisks), the new Zerg Brood was triumphant.

The Overmind created a rift into warp space, and the Zerg travelled through it to Char, a hot planet with many hiding places.

Unsafe Refuge
As soon as the chrysalis arrived, it began to create problems. It had grown much larger and was creating powerful psionic emanations, directed at two Terrans - Arcturus Mengsk and Jim Raynor, for reasons which were, at the time, undisclosed.

Mengsk sent General Edmund Duke with Terran Dominion forces to Char in order to retrieve the chrysalis and acquire the planet's resources for the new Dominion. Zasz was able to intercept Duke's communications and relay them to the Overmind.

Duke was faced by fierce Zerg resistance, as the new Cerebrate tried its hardest to defend the chrysalis. General Duke was forced to retreat, but he remained nearby. Daggoth ordered the new Cerebrate not to pursue, as the Tiamat Brood would take care of that battle.

Rise of a New Power
Jim Raynor was next. Taking a number of Raynor's Raiders with him, he arrived just as the chrysalis was about to hatch. The Zerg once again defeated the Terran opposition, but during the battle the chrysalis split open, revealing the form of the Zerg's newest minion:

Infested Kerrigan, the Queen of Blades! She explained to him that she sent the psionic dreams to him and Mengsk, hoping they would come to Char and rescue her, but they weren't able to do so, and now it's too late. She quickly fell upon the Terrans but allowed Jim Raynor to escape with his life.

Breakthrough
Infested Kerrigan was created as part of the Overmind's plan to use psionic Terrans to help him conquer the Protoss. Unfortunately, her psionic power had been weakened by the Terran Ghost conditioning she had undergone, which was so powerful it survived the Zerg transformation process.

Kerrigan set out to solve this problem. She believed she only needed to collect information on the Ghost conditioning process to relieve her condition. This information could be found on the Terran Dominion science vessel, the Amerigo. Zasz was displeased by her plan, as it was risky, and if she died, the Zerg Overmind's efforts to acquire and transform her would be a failure. Kerrigan had retained the majority of her spirit, however, and ignored his advice.

Onboard the Amerigo, she was accompanied by two of Daggoth's Hunter Killers. She fought the internal security forces, defeating them and even rescuing some Zerglings which the Terrans were still experimenting on. Finally she found the appropriate computer terminal and downloaded the information. Daggoth suggested leaving the Hunter Killers behind, as they would interfere with Terran efforts to recover the now empty vessel.

Test of Wills
Kerrigan defeated the Ghost conditioning and her powers increased. She was able to detect the presence of Protoss on the planet. Tassadar contacted her, and they agreed to a challenge. However, Zasz had detected something unusual about this Protoss, and told Kerrigan she should stay away. Again, Kerrigan would not follow his advice.

Kerrigan's forces disposed of the Protoss base, and she moved to the central arena to challenge Tassadar to single combat. Unfortunately for her, Tassadar had only left an illusion as a distraction. Tassadar told her that she was so predictable, she was her worst enemy. The very angry Kerrigan was then informed by Daggoth that Zasz had died.

Culling
Kerrigan suspected the Overmind would reincarnate Zasz, but Daggoth told her the Overmind had been somehow injured by the strange way Zasz had been killed, and could not speak. Meanwhile, Zasz's now leaderless Garm Brood was running amok, and could threaten the primary Hive Clusters.

The new Cerebrate was ordered to use his forces to destroy the Garm Brood, a task made easier by its lack of leadership.

A new breed, the Defiler, was tested for effectiveness on the Garm Brood. Defilers were created using DNA from all Zerg genera at the time, and resembled ambulatory Zerg larvae. Their complex genetic structure created a wide variety of acids, toxins, diseases and carcinogens which could be used to attack their enemies. The test was successful and the Garm were culled.

A Dangerous Enemy
With the destruction of the Garm the Zerg Overmind awoke and related some very important information. Zasz had been slain by a Dark Templar named Zeratul. Dark Templar used cosmic energies similar to those of the Overmind, and as a result the Overmind could not reincarnate a Cerebrate that had been killed by this method. They could also hide themselves psionically, making it difficult for the Zerg to detect them. However, Overlords and Cerebrates were capable of sensing their presence and leading troops to attack them.

When Zeratul stabbed Zasz with his warp blade, the Overmind was able to contact his mind and read what was within. It now had the location of Aiur in a manner useable to it.

Instead of following its original plan to send Infested Kerrigan to Aiur to help conquer the Protoss, she was tasked with hunting down and killing the Dark Templar. Kerrigan tracked down the main Protoss base on Char and surrounded the escape routes with Overlords, who could detect them. Then the Zerg moved in, destroying the base and the Protoss within. However, neither Tassadar nor Zeratul were present.

The Overmind did not want to wait for its conquest of the Protoss. Leaving Kerrigan behind on Char, it created a giant warp rift and took the majority of the extended Zerg Swarm with it to Aiur.

It promptly launched its invasion force onto Aiur, with the assistance of many Cerebrates, including its newest one. The Overmind's attack was not mindless, however. Without revealing the reasons why, it ordered the new Cerebrate to acquire a Khaydarin Crystal, which was protected by the Shelak Tribe and other Protoss. The force which defended the Crystals, called the "Vanguard of Aiur", was much larger than the Expeditionary Force which the Zerg had fought before. Nonetheless the Zerg defeated the "Vanguard of Aiur" and acquired the crystal.

The Grand Experiment
Finally, the Zerg Overmind was willing to reveal its plan to the Cerebrates. It had been created by the Xel'Naga, as the Protoss had been empowered by them, and was going to add them to the Zerg Swarm as it had many previous species it had encountered. However, the Protoss had a powerful purity of form, just as the Zerg had a powerful purity of essence. Adding Protoss to the Zerg Swarm would give the Zerg both purity of form and essence. The Overmind felt this would made the Zerg "perfect".

In order to physically manifest on Aiur, the Zerg needed to establish itself on a powerful nexus of cosmic energy, found underneath a Protoss Temple which marked the spot where the Xel'Naga first set foot on Aiur. To do so, it needed the Temple to be cleared and the Khaydarin Crystal placed over the nexus.

As the Temple was a very important location for the Protoss, destroying it would grant the Zerg an important psychological victory as well. Again the "Vanguard of Aiur" defended this important resource, this time with help from the Ara Tribe, which acted as a reserve.

The Zerg slowly forced their way towards the Temple, destroying the Protoss defenders. As they attacked the Temple, the Ara Tribe launched their last desperate defense of it. It failed. The Zerg cleared the Temple area and implanted the Khaydarin Crsytal.

Shortly afterwards, the Overmind dived upon Aiur like a bomb. The Zerg conquest of Aiur had begun.