The Dreadbots were built by Major Dr. Ghastly and meant to replace the Henchmen after Hector Con Carne fired them, but General Skarr messed with the technology to make them obedient to him instead of Hector. They were all mindless except for Skarr-bot.
Skarr Jr.EditSkarr Jr. was a Dreadbot that resembled Skarr, who had taken in Skarr-bot as a son. However, Skarr Jr. betrayed General Skarr (using Skarr's own advice and tricks against him) and reprogramed the Dreadbots to be loyal to him.
It is unknown if Skarr had this model built after his takeover, or if Skarr-bot was created beforehand.
The episode ended with a cliffhanger, so it is unknown what became of the Dreadbots. However, as they are never seen again, it is presumed they were defeated and the Henchmen were rehired or replaced with new henchmen.
As replacements for the Henchmen, they were programmed for combat and obedience, but the latter of these functions was shown to be easily tampered with.