R3-S6, also known as "Goldie" or "Stubby," and as "Agent R3" to the Separatists, was an R3-series astromech droid assigned to Anakin Skywalker, during the Clone Wars to replace his lost astromech droid R2-D2. Serving as a double agent for the Confederacy of Independent Systems, R3-S6 often sabotaged Republic missions.