Deep down, below the capital city of Iziz on Onderon, resided the subterranean fortress belonging to King Ommin. After Queen Amanoa was defeated in the battle of Iziz around 4000 BBY, King Ommin withdrew into this fortress. For the next two years, he stayed there, secretly plotting to reclaim Onderon from the Jedi Knights who had aided the Beast Rider army in the overthrow of his deceased wife. The fortress was accidentally found by commander Gobee, a Beast Rider, along with another soldier, while they were exploring the undercity of Iziz. Ultimately, Ommin's fortress met its end in the second battle of the Naddist Uprising, an event that also saw Jedi Knight Ulic Qel-Droma kill Ommin.