The A-series assassin droid was a type of advanced battle droid deployed by the Axis of Empires. It was one of the more advanced and elite models of combat automaton used by the Separatists, and it should not be confused with the more basic battle droid assassin. At 3 meters tall, A-series assassin droids were a lot taller than Humans, and somewhat resembled B2 super battle droids in size and physique. They had an angular humanoid chassis, and lean faces, dominated by four red photoreceptors beneath a sharp, swept-back crest.