The Geonosian Dreadnaught was a Separatist warship, manufactured or used by the Geonosian faction of the Confederacy of Independent Systems.
They were produced in secret factories, and the Galactic Republic first learned of their existence when they were deployed against the Republic some time between the Battle of Geonosis and 21.5 BBY. They were spherical in design, and they were capable of maneuvering down sinkholes on Utapau.
The "Geonosian Dreadnaught" may simply have been an alternative name for or variant upon the Trade Federation's 696-meter Lucrehulk-class core ship.
Behind the scenes
A modified core ship serving as the Separatist headquarters on Utapau.
The term "Geonosian Dreadnaught" is used in a single scene in the novelization of Revenge of the Sith, a scene with no direct parallel in the finished movie, and one which does not fit easily into the internal chronology of the film. Here, General Grievous is standing in his control center on the planet Utapau, which the movie shows to be situated inside a modified core ship dug into the side of a sinkhole, watching the Separatist Council head across the landing deck to board a starship for Mustafar.
Depending on how the passage is read, the Geonosian Dreadnaught could be:
- The headquarters itself, a modified Trade Federation core ship, which is later described from Obi-Wan Kenobi's point of view as "a spiny spheroid of metal: a Dreadnaught-sized structure".
- Another spherical capital ship, perhaps another core ship, that has come down into the sinkhole and parked alongside the lip of the hangar bay to take the Separatist leaders to their new stronghold on Mustafar.
If it is not meant to be a core ship, a Geonosian Dreadnaught is probably closer in size to a Dreadnaught-class cruiser than a larger dreadnought, especially given its atmospheric capabilities and the size-constraints of operating in the sinkhole.
Sources
- Shatterpoint
- Star Wars Episode III: Revenge of the Sith (novel)
Utapau in the Databank (content now obsolete; backup link)