- "We're on Mount Octan. It's a volcano."
"Is the volcano active?"
"I think it's dormant. We should be able to see it and the Skull Queen's fortress when we get to the top of this hill."
- ―Klay Firewell and Anakin Skywalker.
Mount Octan was a volcanic mountain on the jungle-moon of Nallastia that housed the fortress of the ruling Skull Queen, Quenelle (who, as the contemporary Margravine, also served as the Fondorian satellite's political ruler).
The mount, whose conical top "impaled the heavens," was named for the Nallastians' founder, the Margrave Octan, a descendant of the Royal Octans—a ruling family of the Darpa sector, whose traditions of wealth and position extended back to the time of the Old Republic, to the standard years before 4000 BBY. The Margrave's legendary power gems, the Lost Stars of Nallastia, were hidden deep within Mount Octan, in its Cavern of Screaming Skulls.
It was in the grassy foothills of Mount Octan that an 18-year-old Jedi Padawan, Anakin Skywalker, crash-landed a CloakShape fighter that he'd borrowed from Senator Rodd while on a 23 BBY mission to Fondor. Many dangerous creatures, such as the poisonous venrap snake and the wild reptillian grillik, lived in the foothills, but it was here that Skywalker met and befriended Klay Firewell, an 11-year-old boy from Corulag whose zoologist parents were seized by the Nallastian princess Calvaria and imprisoned within an energy field for trespassing. Skywalker bargained for their release and helped in the search for the ancient power gems that would free them.
- Star Wars Adventures 2: The Cavern of Screaming Skulls (First appearance)