The Duel on Vohai took place in 19 BBY between Darth Vader and Emperor's HandSa Cuis, sent by his master Palpatine to kill Vader. However, the duel was in fact a test for Vader, Palpatine's true Sith apprentice. Vader confronted Cuis in the courtyard of Arkanian Microtechnologies after killing several assassins sent by Cuis. Though Cuis put up a furious fight, he was defeated by Vader.