The clash known as the Duel on Vohai happened in 19 BBY, pitting Darth Vader against Sa Cuis, the Emperor's Hand. Palpatine had dispatched Cuis with the intent to eliminate Vader. Yet, the confrontation was actually a trial orchestrated by Palpatine for Vader, his genuine Sith apprentice. After eliminating numerous assassins dispatched by Cuis, Vader encountered Cuis in the yard of Arkanian Microtechnologies. Despite Cuis's intense resistance, Vader emerged victorious.