Nova fighting the Blightbringer within the mines
The Umojan mines were a series of caves on the planet of Jarban Minor mined by the Umojan Protectorate. These caved possessed unusual crystal formations which piqued the Umojan's curiosity. However, when the zerg overran the mining colony, they infested the mines. They became inhabited by a powerful zerg known as blightbringer, who had absorbed a piece of Umojan technology that allowed for the production of holo decoys.
During the Defenders of Man Insurgency, Agent Nova Terra was sent to Jarban Minor to acquire the planet's terrazine, and was asked by Reigel to investigate the mines for lost Umojan technology.
References[]
Blizzard Entertainment. StarCraft II. (Activision Blizzard). PC. Mission: Nova Covert Ops, Night Terrors (in English). 2016-08-02.