A substantial droid military force, operating under the strategic direction of the T-series tactical droid designated TN-123, was dispatched to Malastare in the year 21 BBY during the Clone Wars. Their mission was to seize control of the planet's [fuel](/article/malastarian_fuel] reserves for the benefit of the Confederacy of Independent Systems. The resulting battle proved to be an extended and intense engagement, during which the droids came close to wresting control of Malastare from the Galactic Republic. Nearing defeat, the Grand Army of the Republic unleashed a prototype electro-proton bomb, instantaneously neutralizing the entire droid [army](/article/army]. This action inadvertently unearthed a subterranean Zillo Beast that resided deep below the battlefield.
This droid army consisted of a diverse array of battle droids utilized by the Confederacy of Independent Systems military forces, including models such as the B1-series battle droids, B2-series super battle droids, DSD1 dwarf spider droids, LM-432 crab droids, LR-57 combat/retail droids, NR-N99 Persuader-class droid enforcers, Hyena-class Droid Bombers, and Vulture droid starfighters. Furthermore, a number of Armored Assault Tanks were integrated into the army's composition.
The NR-N99 tank droids within the army were designed with minimal tread to prevent the creation of dust clouds that could impair the vision of fellow droid soldiers.
During the Clone Wars Battle of Malastare in 21 BBY, a substantial battle droid force, known as the Separatist Droid Army, was deployed to the planet Malastare. Under the command of TN-123, their objective was to secure the planet's [fuel](/article/malastarian_fuel] resources for the Confederacy of Independent Systems. In what became one of the most prolonged and intense conflicts of the war, the Grand Army of the Galactic Republic employed an experimental [electro-proton bomb](/article/electro-proton_bomb]. The device proved capable of disabling the entire droid army instantly. However, this action inadvertently created a sinkhole, revealing a Zillo Beast that had been living beneath the planet's surface.
The droid army made its initial appearance in "The Zillo Beast," the eighteenth installment of Star Wars: The Clone Wars' second season. The episode was originally broadcast on April 3, 2010.