Sardis
From Wookieepedia, the Star Wars wiki.
Similar to the Droid Control Ship fielded by the Trade Federation during the Blockade of Naboo, the Sardis acted as both a hangar and control ship for a new generation of droid fighters many times more lethal than the Vulture droids used by the Confederacy of Independent Systems during the Clone Wars.
The Rebel Alliance only encountered the Sardis once, during the Alliance's unsuccessful attempt to destroy the research station Obsidian. However, the Imperials had been caught unaware of the plot, and the Sardis was unable to perform to its peak efficiency either because it was unmanned, or its systems were not yet operational. The research ship was designated a primary target, and it gave no apparent defensive fire as a squadron of B-wings led by Ace Azzameen destroyed it and the station, effectively ending the program.
