The Carbonite Sith Army was an army of Sith troopers that had been frozen in carbonite and put into storage on a rocky planet. At the head of the cavernous chamber where the army was placed in rows, a prominent statue wielding an ignited lightsaber and bearing the emblem of the old Sith Empire at its base had been erected. Soon after the Battle of Endor, the Nightsister Silri rediscovered the army by following information obtained from a Sith holocron.
At an unknown point in time, a host of soldiers that appeared to be Sith troopers were frozen in carbonite and placed in neat rows and columns in front of the statue of an unknown cloaked individual. It was believed that they had survived the process because their carbonite casings were still blinking when they were uncovered during the Galactic Civil War. The troopers were placed inside a large tomb-like cavern, which had been sealed off. A single Sith holocron held the location of the army within its database; when accessed, the information revealed a diagram much like that of a Star Map, which led the user to the planet where the army had been placed.
The great tomb was discovered by the Nightsister Silri not long after the Battle for the Eclipse. She had been examining the holocron, which Tyber Zann and Urai Fen of the Zann Consortium had attempted to steal from Jabba the Hutt on Felucia, and later reacquired after a daring raid on Emperor Palpatine's personal vault on Coruscant. Silri was then able to follow the Star Map to the planet where, after apparently entering a code into a terminal located next to the large stone doorway, the entrance slid open, revealing the army standing in suspended animation.
Though not seen in the cutscene which reveals the frozen army (and therefore may well not be canon), an unknown Sith was also frozen in carbonite. Next to his frozen figure sat an urn, whose contents are unknown. On the lid of the urn sat a lightsaber.
The emblem of the Sith Empire during the Jedi Civil War is on the front of the huge statue at the end of the room. Although the symbol itself is not seen during the in-game cutscene, it can be spotted by examining the object in the Forces of Corruption Map Editor.