Sith wyrm

A massive reptilian insectoid creature that lived on the planet Yavin IV in its large subterranean lair. It was actually a creature altered through the Sith Alchemy of Naga Sadow and designed as a guardian. The ancient Massassi worshipped the beast as a god until it was killed by Exar Kun, who did so to impress Freedon Nadd. It was learnt later that the creature was originally an infant space slug which attached itself to Sadow's battleship.

The creature may have been a one of a kind beast as there are no reports of any sightings of this Sithspawn, a theory supported by Jedi historians.