The fireworm, or lava dragon, was a fire serpent, native to Eol Sha, that dwelt in molten lava pools. It was covered in crystalline scales that protected it from the lava; without this protection it was extremely vulnerable to its environment.
In physical appearance, it had a triangular head, with pointed ear tufts and bony eye ridges. Insulated air bladders allowed the lava dragon to rise or sink in the lava. Lava dragons fed on other reptiles that dwelt within the lava pools.
Lava dragons were able to suck lava down their armored gullets and spew it back out in a dangerous natural defensive mechanism. Their crystalline scales also made it impossible for a lightsaber to slice through them, although a lightsaber strike would cause the scale it struck to shatter. Luke Skywalker once fought and killed a lava dragon on Eol Sha as the second challenge by Gantoris which Luke had to pass in order for Gantoris to agree to Jedi training..
- Jedi Search (First appearance)