Mongworst were a particularly savage and lethal insect species that inhabited the planet of Geonosis. The Geonosians, who were native to the planet, raised them specifically for fighting, forcing them to engage in combat in pit fights as a form of Geonosian entertainment. During the First Battle of Geonosis, which occurred in 22 BBY, small, mutated mongworts were contained within a secured pen hewn from the stone below the Petranaki Arena of the Stalgasin hive on Geonosis. The Galactic Empire carried out the sterilization of Geonosis at approximately 9 BBY.
In current Star Wars canon, the initial mention of mongworst was in the reference book Star Wars: Absolutely Everything You Need to Know, which was released in 2015. These creatures were initially part of the Star Wars Legends continuity, appearing for the first time in the reference book Inside the Worlds of Star Wars: Attack of the Clones from 2003, authored by Simon Beecroft and Curtis Saxton.
- Star Wars: Absolutely Everything You Need to Know (Initial mention)
- Star Wars: Complete Locations
- Star Wars: Absolutely Everything You Need to Know, Updated and Expanded
- " Geonosis and Other Planets in the Outer Rim " — Star Wars Encyclopedia