Grand Preserver

The Grand Preservers were the highest order of the protoss preservers, a very small group of Khalai protoss who held the memories of the dead. Where an ordinary preserver protected the memories of the greatest protoss who had ever lived, a Grand Preserver could navigate the thoughts of every protoss joined to the Khala, and the eldest of them advised the Conclave and shaped the policies of the Protoss Empire. (StarCraft: The Dark Templar Saga: Twilight; StarCraft II: Legacy of the Void)

The preserver caste#

The preservers were a very small group of Khalai protoss based out of the Sanctum, who dressed in gossamer-fine lavender and white garb to make their status plain. Their role was to protect and maintain the memories of the greatest protoss who had ever lived. Though all Khalai could use the Khala, its depth made it difficult for most protoss to hold the focus needed to draw out specific memories, and only preservers had the strength to fully reach into its depths, reaching recollections millennia old. When a Khalai died, their memories transferred instantly to the preservers, and it was claimed that the preservers held access to the memories of every Khalai who had ever lived. (StarCraft: The Dark Templar Saga: Firstborn; StarCraft: The Dark Templar Saga: Twilight)

The psionic link of the Khala was required to become a preserver, so the Dark Templar, who had rejected the Khala, could not join their number. Even so, the preservers could access the memories of protoss from the Aeon of Strife who had lost their connection to the link, and the memories of the Tal'darim of Aiur, who had severed themselves from the Khala with the drug Sundrop, became available upon their deaths. The title of preserver was earned, but it could only be earned by those born with at least some measure of an innate gift, a latent ability present deep within all protoss but expressed fully in only a few. (StarCraft: The Dark Templar Saga: Firstborn; StarCraft: The Dark Templar Saga: Shadow Hunters)

The Grand Preservers of the Empire#

During the era of the Protoss Empire, the highest of the preservers were the Grand Preservers, who could navigate the thoughts of every protoss connected to the Khala. They served both to preserve the memories of ages past and to interpret the thoughts and deeds of protoss long dead, using that wisdom to advise and direct the protoss of their own time. They were very long lived, surviving well beyond a normal protoss lifespan. At least one preserver was always present at the Conclave, and while preservers could offer only information rather than orders and could not themselves sit on the Conclave, their opinions were respected and could shape its policies. (StarCraft: The Dark Templar Saga: Twilight; StarCraft II: Legacy of the Void)

For millennia the wisdom of the preservers was held in the highest regard by protoss leaders. After the Aeon of Strife, the protoss discovered the xel'naga archive world of Zhakul, and when the Conclave took power it sealed away the texts and artifacts of the Aeon of Strife on Zhakul, entrusting them to a trio of preservers. Three Grand Preservers, the sisters Rohana, Orlana, and Shantira, advised the Conclave during the age of Adun and held its respect. (StarCraft II: Wings of Liberty; StarCraft II: Legacy of the Void)

The arkships#

After the khaydarin crystals of two motherships failed and over eight thousand protoss were lost when the craft were destroyed by a neutron star, the Grand Preserver sisters pondered how such small, random events might one day bring down the entire Protoss Empire. They advised the construction of arkships, vessels meant to serve as a last resort against any large-scale tragedy. Three were built: the Spear of Adun, the Memory of Nezin, and the Pride of Altaris. As they reflected further, the Grand Preservers came to fear the arkships had been built too early and would be thrown away early in any conflict rather than held in reserve. They brought this concern to the Conclave, which agreed to bury the arkships on Aiur, each holding a Grand Preserver and a contingent of warriors in stasis. (StarCraft II: Legacy of the Void)

Hunted to near extinction#

Long before the Great War, the Dark Templar Ulrezaj, an Alysaar scholar who tended the memory crystals on the sacred world of Ehlna, accessed forbidden knowledge that drove him mad, and fled rather than have it erased from his mind. After the Brood War, now a dark archon, Ulrezaj used Dark Templar assassins to kill the preservers, whom he regarded as a threat for their knowledge of the xel'naga and the Infinite Cycle. By 2503 there were no preservers among the refugees on Shakuras. The preserver Zamara, mortally wounded by one of Ulrezaj's assassins, forced her mind out of her dying body and into the terran archaeologist Jake Ramsey using the technology of the xel'naga temple on Nemaka, preserving her memories for future generations of preservers at the cost of rewiring Ramsey's brain. Hunted by Ulrezaj, the Queen of Blades, and the Terran Dominion, Zamara ultimately trapped both herself and Ulrezaj within a khaydarin crystal during a ceremony at Ehlna. (StarCraft: The Dark Templar Saga: Firstborn; StarCraft: The Dark Templar Saga: Shadow Hunters; StarCraft: The Dark Templar Saga: Twilight)

Zamara was not the last preserver. A trio of "immortal" preservers lived on Zhakul, but they were captured and drained of their essence by the hybrid Maar, who had also seized control of the Zhakul Guardians. When Zeratul delivered fragments of a xel'naga prophecy to them, Maar tried to stop him and used the preservers' own psionic power to resurrect himself each time he was struck down. Zeratul's forces defeated Maar's servants, rescued the preservers, and felled the hybrid a final time, and the preservers interpreted the fragments so that the Nerazim could continue his quest. (StarCraft II: Wings of Liberty)

Rohana and the reclamation of Aiur#

In 2506 the protoss attempted to reclaim Aiur, only to be halted by the return of Amon and his corruption of the Khala. Hierarch Artanis gathered what forces he could and fled aboard the Spear of Adun, the last surviving arkship, carrying Grand Preserver Rohana, still in stasis. Rohana understood the desperation of the time but refused to sever her connection to the Khala, insisting she would be of more use even if it meant fighting Amon for control of her own mind. She was at first resistant to the changes of the age, in particular the acceptance of the Nerazim, the terrans, and the Purifiers, but she slowly came to understand the times and warm to the other races, calling upon the memories of old executors and judicators to counsel Artanis. (StarCraft II: Legacy of the Void)

Amon used Rohana's connection to the Khala to possess her and speak to the Daelaam aboard the ship, but the attempt backfired: Rohana gazed into his thoughts and uncovered his plan to lure the Daelaam to Aiur and then warp the corrupted Golden Armada down upon them. With that final possession exposed, Artanis convinced Rohana that the time of the Khala had passed and that she had to look to the future, and she severed her nerve cords, ending the last preserver's connection to the collective. Though she could no longer call on the certainty of past protoss memory, Rohana used the deep knowledge of her time as a preserver to oversee the forces reclaiming Aiur, and with her aid the Daelaam took back their homeworld. (StarCraft II: Legacy of the Void)