Duel on Arcadia was a lightsaber duel during the Old Sith Wars in 3,942 BBY, where the recently fallen Jedi and Sith Lord found his former Master, Atris on Arcadia. After Atris gained knowledge of Peter's betrayal on Katarr, Atris arrived on Arcadia and attempted to reason with Balrog, Darth Nihilus controlled Balrog's mind. Balrog no longer cared about the Jedi and his relationship with his master. Balrog claimed Atris as an enemy and later activated their lightsabers and began dueling at the Ruined Temple of Arcadia.