Void

The Void was a dark, cold manifestation of space, separate from the material universe. It appeared to bear a breathable atmosphere to creatures of the material universe and contained landforms akin to floating islands, along with "currents" that could be accessed from ordinary space and that were affected by gravity and solar winds. The Void bore its own lifeforms, including the xel'naga and void shades. It was central to the religion and power of the Nerazim, stood in opposition to the Khala in the cosmology of the protoss, and was where Amon endured and where he was finally destroyed. (StarCraft Field Manual; Ascension; StarCraft II: Legacy of the Void; StarCraft: Shadow of the Xel'Naga)

Nature and hazards#

Void energy was highly unpredictable, and in sufficient quantity it was lethal to both protoss and zerg. It could blind the sensors of the protoss and was capable of changing the physical shape of protoss capital ships. After the Khala was corrupted and Amon gained control of the Golden Armada, carriers and interceptors under his command began to change in appearance from exposure to Void energies, with crystal structures jutting from the carriers' sides. (StarCraft II: Legacy of the Void)

The "currents" of the Void allowed faster-than-lightspeed travel for the Dark Templar, and strands of the Void could be wielded by a Nerazim, who could separate a strand into numerous strands at will. (StarCraft: Shadow of the Xel'Naga; Lens of the Void)

The Nerazim and the Void#

The Void was understood above all by the Nerazim. When they severed their nerve cords in a display of contempt for the Conclave, they lost the primal link the rest of the protoss shared and removed themselves from the control and discipline the Khala provided. Forced to live in secrecy to avoid detection by the Khalai, and without the psionic focus the Khala afforded, the Nerazim turned instead to the mysteries of the Void, eventually learning to wrest its power through rigorous training, discipline, and will. (StarCraft (manual); StarCraft: The Dark Templar Saga: Shadow Hunters; Dark Templar (StarCraft II official site))

The Void granted the Nerazim psionic powers unheard of by their brethren. It also demanded will and discipline in return, for a Nerazim who lacked these traits could be consumed by it. Those who walked the path did so with diligence and reverence, knowing the dangers lurking in the shadows of the Void. The warp blades wielded by Nerazim warriors were infused with Void energy. (StarCraft: Shadow of the Xel'Naga; Dark Templar (StarCraft II official site))

In their culture, the Nerazim associated the Void with death or the afterlife. To "embrace the Void" was to embrace death, and many believed that as one came close to death, one came closer to the Void. Some took to using immortal technology to keep themselves in a state of near-death indefinitely, gaining a greater connection to the Void in the process. They considered anything that tainted the Void to be unholy, and the Void formed a major part of their religion. The texts the Nerazim wrote when they first studied the Void became the basis of their teachings centuries later. To the Khalai, by contrast, the Void appeared to serve as a negative afterlife, a place where the consciousness of those who did not join the bliss of the Khala were damned. (Lens of the Void; StarCraft II: Legacy of the Void; StarCraft: Frontline Volume 4; Carrier)

The Void and the Khala#

Wielding the Void and the Khala simultaneously granted a protoss incredible power, but could cause the wielder to burn out like a star. Protoss able to use both sets of power at once were exceedingly rare; the known practitioners were Adun and Tassadar. The prismatic core of the void ray likewise drew on the Void and the Khala in tandem, forming a self-sustaining reaction that made the core a virtually eternal power source. (StarCraft: The Dark Templar Saga: Shadow Hunters; StarCraft; Lens of the Void; Void Ray (StarCraft II official site))

The Tal'darim had a different relationship with the Void. They believed that Amon resided within the Void and that it was only through his blessing that one could travel through it. From the Void they drew the energy for their bane blades, which were composed of pure Void energy, and they regularly used terrazine, a substance originally from the Void, to enhance their powers. (Ascension)

The xel'naga#

The xel'naga arose within the Void and understood their domain, and their ships possessed the ability to travel through it. They imprisoned the KL-2 entity using the powers of the Void. When the physical body of a xel'naga was killed, its mind survived within the Void and could be revived with enough psionic energy, as happened with Amon. For this reason the only way to truly kill a xel'naga was to destroy it within the Void itself. Amon was further able to use Void energy to shield his forces and increase their fortitude. (StarCraft II: Legacy of the Void; StarCraft: Shadow of the Xel'Naga; StarCraft: Frontline Volume 4; Ascension)

The Void was also inhabited by a mysterious entity at KL-2 calling itself the "Heart of the Void," which the Nerazim said had "tainted" the Void. (StarCraft: Frontline Volume 4)

The expedition into the Void#

In 2506, the Terran Dominion, Zerg Swarm, and Daelaam launched a joint expedition into the Void to slay Amon, using Ulnar as a void portal. They fought through void entities that tore at their forces, but were eventually successful in allowing Sarah Kerrigan to ascend into a xel'naga and slay Amon in the one place where he could be permanently destroyed. (StarCraft II: Legacy of the Void)