They were often used as assassins and were equipped with built-in blaster, explosive projectiles, and blades and spikes for close combat. The droids were 2.3 meters tall. They were designed for security and military duties, and were known to be determined and effective fighters. One drawback of the design was the hands, which required the droid to use specially designed weapons. It was also limited due to its large size, which could hinder its ability to move or use small objects.
One droid, FLTCH R-1 was dispatched by Representative Bron and Ephant Mon to assassinate Cerean Jedi Knight Ki-Adi-Mundi. Ki-Adi-Mundi defeated the droid and had it reprogrammed to work for him in hunting down Mon.
- Star Wars: Republic 3: Prelude to Rebellion, Part 3 (First appearance)
- Star Wars: Republic 4: Prelude to Rebellion, Part 4
- Star Wars: Republic 5: Prelude to Rebellion, Part 5
- Star Wars: Republic 6: Prelude to Rebellion, Part 6
- Star Wars: Republic 8: Outlander, Part 2
- The Official Star Wars Fact File 115 (Merc Droid)
- "Unknown Soldier: The Story of General Grievous"—Star Wars Insider 86
- The New Essential Guide to Droids
- Jedi Academy Training Manual
- Scavenger's Guide to Droids (First identified as FLTCH-series battle droid)