Led by Hun-grrr, they appeared with no formal introduction, They were quickly defeated by the technobots and their gestalt-form Computron, again and again.
IDW Publishing Continuity
The Terrorcons looked up to Sixshot for how destructive he was. One day, they were captured by the Reapers on Mumu-Obscura. Sixshot would head there and fight the Reapers only to learn that they were testing him to see if he was worthy of joining them. The Terrorcons were then revealed and the Reapers told Sixshot that his final test to join them was to kill. Sixshot then shot at the Terrorcons but intentionally missed them.