AK-Prime was a battle droid found in the crater of a volcano on the planet Mustafar during the Galactic Civil War. It was there that he defended HK-47 from a group of spacers, though he eventually failed and was destroyed. AK-Prime was similar to his lesser, but still effective, AK-3 Reaper, AK-1A Hammer, CLL-8 Combat Droids, and, oddly enough, CWW-8 Load Lifter Droids, upon which the design was based.
AK-Prime sported a wide range of weaponry, including Republic Sfor Carbines, a plasma flamethrower, and rocket launchers. He also had the ability to send out a shockwave, knocking down his opponents. This proved to be a nuisance to spacers who tried, successfully, to stop him.