The IG-series was a line of battle and assassin droids produced by Holowan Laboratories and its subsidiary, Holowan Mechanicals, though some of their components (including the head parts) were in fact of Incom Corporation make.
Assassin droids were illegal for centuries, under the Galactic Republic. After having found success in the last years of the Republic and during the Clone Wars, the designers at Holowan Laboratories believed they would be able to control their overpowered IG-88 assassin droid line, but the programming was faulty.
There were four IG-88 assassin droids, labeled A, B, C and D, only one of which was loaded with the programming. As the programming was loaded into unit A, it self-replicated itself. As the droid came online, it perceived the scientists as a threat and eliminated them. It then copied its programming into units B, C, and D. The droids killed everyone at the facility and released IG-72, who left the four IG-88 droids to track down and destroy their programmers, as well as their notes to prevent anyone from learning their weaknesses. The droids then went separately into the galaxy to become bounty hunters. Though all were ultimately destroyed when they tried to take Han Solo from Boba Fett, IG-88A transferred its mind into the second Death Star's computer core; this was destroyed in the explosion of that base.
- LEGO Star Wars: The Video Game
- LEGO Star Wars: The Complete Saga
- LEGO Star Wars II: The Original Trilogy
- "Skippy the Jedi Droid"—Star Wars Tales 1
- LEGO Star Wars III: The Clone Wars
- Galaxy Guide 3: The Empire Strikes Back (As "IG line")
- The Movie Trilogy Sourcebook (As "IG line")
- The Secrets of Star Wars: Shadows of the Empire
- Galaxy Guide 3: The Empire Strikes Back, Second Edition
- Cynabar's Fantastic Technology: Droids
- The Official Star Wars Fact File 4 (ASS1–2, IG-88 Assassin Droid)
- Star Wars Galaxies: The Total Experience: Prima Official Game Guide
- Star Wars Galaxies: The Complete Guide: Prima Official Game Guide
- The New Essential Chronology
- The New Essential Guide to Characters
- The New Essential Guide to Droids
- The Essential Guide to Droids
- Star Wars: Edge of the Empire Core Rulebook
- Enter the Unknown (Picture only)
- Star Wars: Age of Rebellion Core Rulebook