The Void

The Void was a dark, cold manifestation of space, separate from the material universe. It was the place from which the xel'naga first arose, the wellspring of the shadow powers wielded by the Nerazim, and the only place where a xel'naga could be truly and permanently destroyed. Connected to the material universe through sites such as Ulnar, it was as much a part of protoss religion and dread as it was a physical place. (StarCraft Field Manual; Ascension; StarCraft II: Legacy of the Void)

Nature of the Void#

The Void appeared to bear a breathable atmosphere to creatures of the material universe and gave rise to its own lifeforms, among them the xel'naga and void shades. Landforms existed within it like floating islands, and currents of the Void, affected by gravity and solar winds, could be accessed from the material universe. Void energy was highly unpredictable and, in sufficient quantity, lethal to both protoss and zerg, capable of blinding protoss sensors and even of reshaping their capital ships. During the End War, after Amon corrupted the Khala and seized the Golden Armada, carriers and interceptors under his control began to warp in appearance from the exposure, crystal structures jutting from their hulls. (StarCraft II: Legacy of the Void; StarCraft: Shadow of the Xel'Naga)

The Nerazim and the Void#

The Void was most deeply understood by the Nerazim. Having severed their nerve cords in contempt of the Conclave, they lost the link that the rest of the protoss shared and the focus the Khala provided. Forced to live in secrecy and without that focus, they delved into the mysteries of the Void and learned to wrest its power through rigorous training, discipline, and will. The Void granted them powers unheard of by their brethren, but it could consume those who lacked the discipline to wield it. Its currents allowed faster-than-light travel for the Dark Templar, its strands could be separated and wielded as weapons, and its energy infused the warp blades of their warriors. To the Nerazim the Void was bound up with death and the afterlife, and to embrace the Void was, in their language, to embrace death. (StarCraft (manual); StarCraft: The Dark Templar Saga: Shadow Hunters; Dark Templar (StarCraft II official site); StarCraft: Shadow of the Xel'Naga; Lens of the Void)

The Void and the Khala#

To wield the Void and the Khala at once granted a protoss incredible power, but at the risk of burning out like a star, and those who could do so were exceedingly rare. The only known practitioners were Adun and Tassadar, the latter channeling both energies to destroy the first Overmind. The prismatic core of the void ray drew on the Void and the Khala in tandem, forming a self-sustaining reaction that made the core a virtually eternal power source. To the Khalai, by contrast, the Void served as a negative afterlife, a place where the consciousness of those who did not join the bliss of the Khala were thought to be damned. (StarCraft: The Dark Templar Saga: Shadow Hunters; StarCraft; Lens of the Void; Void Ray (StarCraft II official site); Carrier)

The xel'naga and the final death#

The xel'naga arose within the Void and understood it as their domain, and their ships could travel through it. When a xel'naga's physical body was killed, its mind survived within the Void and could be revived with enough psionic energy, as happened with Amon; the only way to truly kill a xel'naga was therefore to destroy it within the Void itself. The Tal'darim believed Amon resided there and that it was only through his blessing that one could travel through it, drawing the energy for their bane blades from pure Void energy and using terrazine, a substance originally of the Void, to enhance their powers. In 2506, the Terran Dominion, Zerg Swarm, and Daelaam launched an expedition into the Void to slay Amon, using Ulnar as a portal. They fought through void entities that tore at their forces and ultimately allowed Sarah Kerrigan to ascend into a xel'naga and end Amon for good. (StarCraft II: Legacy of the Void; StarCraft: Shadow of the Xel'Naga; Ascension)