During the time of the Clone Wars, the droid army of the Confederacy of Independent Systems kept a specific unit of battle droids stationed at the Citadel prison on the planet of Lola Sayu. This unit was under the command of Commander Osi Sobeck and comprised various models of battle droids, such as B1-series battle droids, B2-series super battle droids, droidekas, BX-series droid commandos, OOM-series security droids, LM-432 crab droids, Ringneck recon droids, and multiple packs of anoobas. They also utilized Single Trooper Aerial Platforms, and the unit consisted of a minimum of ten squads alongside several droid battalions.
In 20 BBY, the Galactic Republic sent a specialized team to Lola Sayu with the goal to break into the Citadel. Their mission was to rescue Jedi General Even Piell and his associated Republic forces, who had been imprisoned there by Separatist forces seeking to acquire the coordinates for the vital Nexus Route. However, while operating inside the Citadel, the Republic strike team encountered the aforementioned droid unit multiple times. These encounters occurred as the droids attempted to prevent the Republic team from escaping the planet with the strategic information. Consequently, the Citadel forces, acting on orders from Citadel Command, initiated all security protocols within the prison to thwart the Republic team's escape.