Sarah Kerrigan

"Artanis! WAIT! I am not your enemy...."

- Kerrigan to Artanis before fighting the hybrid.

"I am the swarm. Armies will be shattered. Worlds will burn. Now at last, on this world, vengeance shall be mine. For I am the Queen of Blades."

- Kerrigan leading the Zerg.

Sarah Kerrigan is the protagonist (in some missions) in Starcraft 1 (until fallen at Mission 9) and in Starcraft 2: Heart of The Swarm (redeemed at the end of Wings of Liberty).

Despite knowing that her humanity would be lost again, Kerrigan agreed to this. She allowed Zurvan to lead her to the first spawning pool where the zerg had first evolved. Against Abathur's advice, she entered the pool to begin her transformation. Before sealing herself within a chrysalis, she ordered her minions to defend her until she either emerged from the chrysalis or was dead. She hoped that in her new form, Amon would exert no influence over her mind. The primal zerg ferociously assaulted Kerrigan's position, but Kerrigan's zerg held them off long enough for the transformation to be complete. Kerrigan emerged from the chrysalis as the Primal Queen of Blades; making her presence known to all of Zerus.

Upon returning to her leviathan, Kerrigan was met by Dehaka, a primal zerg pack leader who wished to join her Swarm, pledging to serve her in exchange for new sources of essence. Kerrigan accepted Dehaka and his pack into the Swarm. Dehaka informed her that the other primal pack leaders would not submit to Kerrigan and thus, had to be eliminated. Although Yagdra, Kraith, Slivan and their respective packs fought viciously against Kerrigan's Swarm, they were ultimately no match for the reborn Queen of Blades. After collecting their essences, Kerrigan was confronted by Zurvan, who initially acclaimed her for her victory. He then turned on her, with the intention of consuming her essence; explaining that he had "no allegiance but to self". Kerrigan expected his challenge and killed Zurvan, thus fully claiming the power of all Zerus. With her mission on Zerus complete, Kerrigan ordered Izsha to prepare the leviathan to return to the Koprulu sector.

The Queen's Return
Kerrigan's broodmothers delivered a communicator, and, on cue, a message from Arcturus Mengsk was delivered. Mengsk told her that Raynor was alive, but that if she brought her Swarm to bear against Korhal or him, Raynor would be killed. Kerrigan couldn't sense Raynor, but swore that she'd rescue him, and set a course for Dominion space.

Skygeirr
Kerrigan was contacted by an unknown entity, who claimed to know of Kerrigan's desire to topple Mengsk. The figure told her that her chances of defeating Mengsk were nullified as long as his hybrid were alive and that defeating them was a top priority. Kerrigan tracked the figure to Skygeirr Station, and upon arrival, she questioned its identity. It revealed itself to be an infested Alexi Stukov.

He told her that Narud was in fact a shapeshifter who "had worn many faces over the years" and served Amon. Stukov claimed that Narud had made him into whom he was and that he was the victim of countless experiments by Narud. To destroy the lab, Kerrigan first needed to destroy the Dominion garrison protecting the lab's topmost level, which was protected by infantry and heavy weapons. To this end, she utilized infestors to spawn infested terrans at the garrison's complement. The terrans used gas to wipe out the infested, but there was a delay between each usage of the gas. In the end, Kerrigan's zerg destroyed the garrison and then entered the lab.

On the lower level of the lab, Narud unleashed eight hybrid dominators to psionically sap Kerrigan's life. They were defeated, as was the Dominion garrison entrenched at the same level. Kerrigan then ordered the Swarm to flood the remaining levels of the lab and eradicate everything within. However, the lab was built atop a xel'naga temple, and here the Swarm encountered protoss Tal'darim warriors who worshiped Amon and served him. Narud personally tried to kill Kerrigan with a null-zone, which Kerrigan countered with her own. Narud drew power from several xel'naga temples located throughout the level. With Kerrigan locked in combat with Narud, Stukov was left to lead the zerg to destroy the temples. The protoss attacked the zerg, reinforced by hybrid reavers, but ultimately, the zerg prevailed. Eventually, Stukov deactivated all of the xel'naga temples and Narud lost the null-zone battle. He retreated even deeper into the temple, where he was confronted by Kerrigan. Morphing first into Raynor and then Kerrigan's pre-infestation form, he nearly killed her with a psi-blade but in turn, Kerrigan fatally wounded him with her wings. Before dying, Narud told her that Amon was alive, and that she would encounter him soon. It was the truth, for as Kerrigan looked into Narud's mind, she realized that Amon had indeed been resurrected.

Kerrigan was brought back to the leviathan to be healed. She revealed what she had learned from Narud, that Amon was alive, and was a threat to the zerg. Once Mengsk was dealt with, they would have to face him in turn.

Reuniting with Raynor
Kerrigan made contact with the Hyperion. Matt Horner and Valerian Mengsk were shocked to see that Kerrigan had returned to her zerg form, but agreed to help her find Jim. After retrieving Colonel Orlan from Mira Han, they forced Orlan to hack into the Dominion's network and locate Raynor. They learned that Jim was being held aboard the prison ship Moros which was currently docked at Atlas Station. Kerrigan launched an assault on the Moros and boarded it.

Mengsk attempted to kill both of them by triggering a self-destruct without the crew's knowledge, but Kerrigan was able to use her leviathan to stabilize the section where Raynor was being held. Raynor was horrified to see that Kerrigan had willingly reinfested herself, and brushed off her justifications by reminding her of Fenix's murder, as well as the millions of others she had murdered in cold blood, to which she offered no defense. Kerrigan gave him his gun, put it to her forehead, and told him that he was both the one who swore to kill the Queen of Blades and the one who believed in her. She asked him if he still believed in her. After some hesitation, Raynor fired...again and again. Yet for all that, he couldn't, or wouldn't, hit her. Kerrigan told Raynor that she would always love him, but he coldly declared their relationship was over.

Vengeance
With Narud and his hybrids destroyed and Raynor saved, Kerrigan ordered the swarm to invade Korhal. The swarm surrounded Korhal with dozens of leviathans, preventing reinforcements from getting through.

Kerrigan's first priority was to destroy Korhal's planetary defenses. She had Abathur devise the bile launcher, a modified virophage that could destroy the defense cannons from a long range. However, the launchers themselves had to be planted on the surface. Thus, Kerrigan unleashed millions of drop pods upon Korhal. Though many were shot down, a sufficient number landed on the outskirts of Augustgrad. Kerrigan herself entered the fray and secured the landing site of the bile launchers that eventually destroyed the Dominion defense, allowing the rest of the swarm to land and drive the Dominion into the city.

At this time, Mengsk activated his newest weapon: The Psi Destroyer. This device emitted a field that could kill the zerg through their psionic connection to a hive mind. Having anticipated this, however, Kerrigan, sent Dehaka and his primal zerg (who had no hive mind connections) to take out the Destroyer's power generators. The swarm then eradicated the dormant weapon and its defenders.

After conferring the final attack plans with her lieutenants and one last communication with the Hyperion, Kerrigan invaded Augustgrad. On Prince Valerian's request, Kerrigan slowed her invasion to let Korhal's civilians evacuate unscathed. The zerg encountered heavy resistance from the Dominion's elite guard, who possessed enhanced weapons, as well as the Odin. Unexpectedly however, Raynor and the Hyperion came to Kerrigan's aid. With the combined might of Raynor, Zagara, Dehaka and Stukov, Kerrigan erradicated Mengsk's defenders and breached the palace. She ordered Zagara to take command of the swarm while she entered the palace to deal with Mengsk alone.

Inside the palace, Kerrigan cut her way through Mengsk's final defenses and made her way to Mengsk's office at the top where the emperor was expecting her. He brought his last weapon to bear: the xel'naga artifact, though this time he planned to use it to destroy her directly. Mengsk used the device to disable and torment Kerrigan while gloating, calling Kerrigan his greatest failure. Unfortunately for the tyrant, his gloating allowed Raynor to intervene in the nick of time; he crushed the control for the artifact and threw Mengsk across the room. Enraged, Kerrigan impaled Mengsk to the wall by his shoulders and after a final bitter exchange of words, overflowed him with her psionic energies. Mengsk exploded violently, blasting a massive hole through the wall behind. Though she departed Korhal immediately following Mengsk's death, she thanked Raynor "for everything" he'd given her before she left.

Her vengeance fufilled, all that remained for Kerrigan was to send the Swarm against its true enemy, Amon.

Legacy of the Void
During Amon's war against the denizens of the Milky Way, Kerrigan was attacked by a hybrid reaver, which was (at least temporarily) able to gain the upperhand over her. She also encountered Artanis during the conflict. In the end of Epilogue, she began exterminating Amon for good.