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The Scion provided transport for Torch Seven for their mission to Vygoire, transmitting orbital imagery of the lab complex they were assigned to investigate. During the initial recon, the Scion was called out-system for emergency escort duty, but advised the unit that it would contact them when they were back in-system.
Things went bad on the ground, as Torch Seven suffered over 33% casualties from contact with an ultralisk. Its request for extraction was denied however, as per the Scion's atmospheric limitations, not to mention that it would take a few hours to arrive. The unit was ordered to take out the ultralisk before dropships were deployed.
Later, the Scion returned and launched a dropship, but it still refused to land until the ultralisk was dead. Eventually, the squad took down the ultralisk, and the dropship picked up the eleven survivors.
On board the Scion, Vera Langridge, survivor of the mission, killed all of the remaining Torch Seven squad members except Sergeant Norwood Doakes. Doakes had been infected by a type of psychoactive spore, while Langridge apparently remained immune. Langridge was assigned to interrogate Doakes to gain info on the spores while the battlecruiser's crew was put under quarantine until further notice. The Scion then nuked the planet in order to prevent the spread of any more of the spores or zerg on the surface. The battlecruiser's commander pressed her for details, but she stated she could not tell him who she was working for.