IG-88C was created on Halowan by the Holowan Mechanicals Company in the Project Phlutdroid. After a droid of identical model called IG-88A turned against his biological creators, he then proceeded to activate and copy his programming into the other inactive droid's empty computer cores. A named the other droids by letter in order of activation. IG-88A designated him IG-88C. All the assassin droids then continued to escape the laboratory, with the help of an assassin droid of similar model, called IG-72, who denied the option of joining them on their mission but would help them escape. They then took a courier, escaped the planet, and set their sights on the foundry world of Mechis III.
The IG-88s managed to get all of the droids to kill the 73 organic sentients on the planet by slicing into the planet-wide defense grid. They then began reprogramming all the droids on Mechis III, so that they would have sentience programming, and obey their orders. Then they began to manufacture droids with embedded sentience programming so that when IG-88 transmitted the signal, all the droids they manufactured would turn against their biological masters, thus taking over the galaxy. Thus was the beginning of the IG-88s' Droid Revolution.
With IG-88A impersonating the now-deceased administrator of Mechis III and IG-88B acting as the bounty hunter "face" of the group, IG-88C and D were left to personally oversee the manufacturing of their plan and act as sentries for Mechis III. Soon after IG-88B was destroyed, C and D attacked Boba Fett en route to Jabba Desilijic Tiure above Tatooine to steal Han Solo's carbonite block in 3 ABY and avenge their lost "brother". Boba Fett turned against C in Slave I and fired every weapon in his ship's arsenal. Seeing as how IG-88C thought that Fett's moves were "highly illogical", he could not—and did not—predict it and was destroyed.
- Therefore I Am: The Tale of IG-88
- Star Wars 50: The Crimson Forever (First appearance)
- Shadows of the Empire 1 (Indirect appearance)
- A Barve Like That: The Tale of Boba Fett (Appears in flashback(s))
- Galaxy Guide 5: Return of the Jedi (as IG-88)
- Galaxy Guide 5: Return of the Jedi, Second Edition (as IG-88)
- Shadows of the Empire Sourcebook
- Galaxy Guide 3: The Empire Strikes Back, Second Edition (Indirect mention only)
- The Essential Guide to Droids (Mentioned only)
- C-3PO: Tales of the Golden Droid (Indirect mention only)
- Aurra Sing: Dawn of the Bounty Hunters
- The New Essential Guide to Characters
- The Official Star Wars Fact File 4 (ASS1-2, IG-88 Assassin Droid)
- The Official Star Wars Fact File 22 (ASS3, IG Assassin Droids)
- The New Essential Guide to Droids
- The Complete Star Wars Encyclopedia
- Rebellion Era Campaign Guide
- Star Wars: The Official Starships & Vehicles Collection 23
- Star Wars: The Ultimate Visual Guide: Updated and Expanded
- Star Wars: Force Collection (Card: IG-88B (★★★★)) (Indirect mention only)
- Star Wars: X-Wing Miniatures Game – IG-2000 Expansion Pack (Card: IG-88C—Aggressor)