The marriage of repulsorlift technology and heavy armor has resulted in formidable floating tanks known as AATs. These assault tanks form the frontline of Trade Federation armored infantry divisions, as well as Separatist forces during the Clone Wars. A crew of battle droids drives the battle tank and operates the array of laser and projectile weaponry carried by the vehicle.
Rather than use flesh-and-blood warriors, the Separatists prefer mindlessly loyal soldiers that are easily controlled. The soulless ranks of their armies are dominated by tall, thin B1 battle droids built as mechanical imitations of their Geonosian designers. Battle droids can be controlled by centralized command centers such as the Trade Federation’s enormous Droid Control Ships, or programmed for independent action. They often suffer programming glitches that manifest as personality quirks. Battle droids are dim-witted and no match for clone troopers or Jedi, but they weren’t designed to be smart – they were designed to overwhelm Republic civilians through sheer numbers, something they do very effectively.
The infantry used by the Trade Federation had several major shortcomings that were carefully revisited by the battle droids' designers. From that research came the super battle droid, a bulkier, stronger, and more advanced version of the standard mechanical soldier. The super battle droid requires no overriding command signal to operate, and thus has a limited degree of independence. They are fearless and tireless, and will run at full speed into combat, their cannons extended, firing until they have reduced their targets to smoldering ruins.
At over three kilometers in diameter, these enormous vessels resemble flattened disks with a central sphere containing the ship's bridge and reactor assemblies. The disk is broken at the front of the craft, revealing two mammoth docking bays lined with forward docking claws. The reclusive Neimoidian commanders typically seal themselves in the ship's spacious bridge while their legions of droids handle the operation of the mighty craft. The most important vessel in a Separatist battleship flotilla is the Droid Control Ship, which transmitted signals to the battle droid armies used by the Trade Federation and Separatist forces.
One of the wealthiest corporate organizations in the galaxy, the Trade Federation controlled most of the interstellar shipping passing through the Rim territories. The Trade Federation was headed by Viceroy Nute Gunray, and even had its own representative in the Republic Senate to lobby for even greater power. On the orders of Darth Sidious, the Trade Federation sent its battle droids to invade Naboo to create a government crisis. During the Clone Wars, the Trade Federation secretly signed on as a member of Count Dooku's Separatist organization, though representatives in the Senate tried to deny this.
In the final days of the Republic, the galactic government had grown so huge and corrupt that any attempt at change required radical thinking and extreme actions. Outlying systems that saw no benefit from being part of the Republic despite paying heavy taxes, began to rebel. This undercurrent of disgust towards Coruscant was seized by a charismatic leader, Count Dooku. The former Jedi rallied together these worlds in a Separatist movement that saw the departure of thousands of systems from the Republic. When Dooku's alliance was secretly backed by corporate titans that offered their unlimited droid armies to the cause, the Separatists emerged as a major threat to the Republic, and the galaxy tipped towards full scale war.