The Battle of ThonBoka was a battle in 3 BBY between the Oswaft and the Galactic Empire. ThonBoka was a sack-shaped nebula within a client state of the Empire known as the Centrality. It was home to the gigantic spacefaring Oswaft species. The Centrans had known of the species for generations but the aliens had not come to Palpatine's attention until just prior to Lando Calrissian's arrival in Dela, the financial hub of the Centrality.