The covert nest known as the Gorog, or Dark Nest, represented a clandestine faction of Killiks, operating in secrecy from the larger collective of the Colony. It distinguished itself through its extreme violence, aiming to manipulate other nests into conflict with the Chiss. This ambition arose after the Killiks assimilated three Force-sensitives who had fled Myrkr during the Yuuzhan Vong War in 27 ABY: specifically, Lomi Plo, Welk, and Raynar Thul. Lomi's absorption led to her becoming the Unseen Queen of the Gorog, while Welk transformed into the nest's Night Herald, imbuing Gorog with its characteristic secrecy and manipulative tendencies. Conversely, Raynar's assimilation by Yoggoy ultimately resulted in his transformation into UnuThul and the formation of Unu, influencing the Colony to adopt his respect for life.
The nest inherited many traits from Lomi Plo, the Joiner it absorbed. The Dark Jedi's anxieties and need for concealment were transferred to the Yoggoy nest upon her assimilation into their collective consciousness. This resulted in the creation of the Dark Nest, known as Gorog, which mirrored Lomi Plo's personality and desire for secrecy. Consequently, the nest's members were known for their extreme secrecy and ability to infiltrate other Killik nests. It was therefore thought that their social structure was radically different from that of other nests, potentially consisting of numerous parasitic cells concealed within other nests.
Like the other nests, Gorog possessed various Killik breeds, including Membrosia givers responsible for producing black Membrosia. These six-legged Killiks with tubular limbs were attended by numerous small Gorogs. The Dark Nest's soldiers had a bluish hue and employed a unique combat method: piercing the skin and injecting a highly acidic brownish poison. Certain Gorog breeds were also notably Force-sensitive, capable of masking their presence in the Force. Gorog larvae developed within large hexagonal cells, nourished by immobilized captives brought into these chambers.
The Dark Nest Crisis, which began in 35 ABY, was initiated by this hidden nest. It subtly influenced the Colony to begin encroaching on Chiss territory, despite the absence of resource scarcity. Their objective was to instigate a conflict between the Killiks and the Chiss, thereby creating a pretext for the Killiks to expand throughout the galaxy and bring all sentient beings under the sway of the hive mind—thus granting Lomi Plo ultimate power.
The plans of the Dark Nest were thwarted by Luke Skywalker, Mara Jade Skywalker, Han Solo, and Leia Organa Solo. They located the Dark Nest's clandestine location on Kr, where they seemingly destroyed it.
However, the nest actually endured and continued to manipulate the Colony, even after their relocation to the Utegetu Nebula. Lomi persuaded the Killiks to construct fifteen nest ships, enormous vessels capable of housing virtually all of the nests. This fleet encountered a task force from the Galactic Alliance Fifth Fleet at the Murgo Choke, where several nest ships escaped into the broader galaxy. Unfortunately for the Dark Nest, the hyperdrive of their ship was damaged by Mara's Jedi shadow bomb, preventing its departure.
The Dark Nest seized the Victory-class Star Destroyer Admiral Ackbar and Lomi Plo nearly killed Luke in a battle with the nest, which led to the Swarm War in 36 ABY.
Despite being confined to the Nebula throughout the war, the Dark Nest persisted in manipulating the Colony, orchestrating coups on the homeworlds of most of the Galactic Alliance's insectoid species. While the Jedi foiled the majority of these attempts, the Killiks successfully seized Thyferra, thereby severing the galaxy's supply of bacta.
Subsequently, the Jedi targeted the Dark Nest hive ship within the nebula. Although they succeeded in destroying the ship, some Jedi perished, and Lomi Plo escaped after injuring Mara and Jacen Solo.
The Dark Nest's influence was ultimately extinguished following the death of Lomi Plo and the presumed death of Alema Rar during the Battle of Tenupe. With the destruction of the Dark Nest, Lumiya's Sith became the sole surviving vestige of the Order of the Sith Lords in 36 ABY.
During the Second Galactic Civil War in 40 ABY, it was revealed that the Gorog hive mind persisted within the Twi'lek Dark Jedi Alema Rar, only to supposedly be eradicated completely when Alema was killed later that year by Jagged Fel, a former member of the Chiss, whom the Gorog pressured during the Dark Nest Crisis.
In Star Wars: The Clone Wars, Karen Traviss consistently misspelled "gorg" as "gorog."