Empirical

The ISS Empirical was a mobile research laboratory, a modified cruiser that belonged to Darth Vader. Rumoured to be one of many such vessels used by the Dark Lord, the Empirical housed the cyborg's experiments on prisoners and studies conducted on unique alien species. Top-secret, moving only between lifeless star systems in the Outer Rim Territories and escaping even the eyes of Emperor Palpatine's spy network, the vessel was crewed by a platoon of soldiers of the Galactic Empire personally selected by Lord Vader, who monitored the test subjects and eliminated those that escaped confinement before they could get off the ship. One of the many such experiments was Lieutenant Rom Mohc's Dark Trooper Phase Zero project, which operated out of the Empirical until it was shut down for practical reasons.

When Vader's apprentice Galen Marek was injured close to death on the orders of Palpatine, Vader brought him to the Empirical to be rehabilitated, bringing along Marek's ship, the Rogue Shadow, and his droid, PROXY. Vader later sent Marek's pilot, Juno Eclipse, to the vessel after she was arrested for treason. When Marek awoke after six months, PROXY helped him escape the vessel, kill many of the crew—who thought he was one of Vader's experiments and had orders to terminate him—and free Eclipse. Under orders from Vader to remove all evidence that Marek had been there, including the crew, PROXY disabled the ship's navigational systems and set it on a course into the Dominus system's primary star. Marek, Eclipse, and PROXY escaped on the Rogue Shadow as the Empirical plunged into the star and exploded.

Text and facts from the “Empirical” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.