1000 years ago, Baron Karza was the head scientist of the royal academy of Homeworld in the Microverse. He was one of the first instructors of Prince Arcturus Rann, and helped him prepare for his 1000 year mission to explore The Microverse. In the intervening years while Rann was away on his mission, Karza killed Rann's parents King Dallan and Queen Sepsis, and used his super advanced technology to completely subjugate Homeworld and a good portion of the Microverse. Karza's creation of the Body Banks allowed him to harvest limbs and organs, recycling corpses and living beings alike to extend the lifespan of anyone who was willing to pay. He created a military force of Dog Soldiers to enforce his will and to help maintain order within his empire. Over the years Karza has proven himself a master strategist, and a source of pure unadulterated evil that has a nasty habit of turning up again just after it seems everything is recovered from his last resurrection.
Baron Karza was based off the Mego Toy Baron Karza (1977). Mego's Baron Karza toy was a repaint with a slight re-tooling of the head sculpt of the Microman toy Jeeg (1975). Jeegwas Takara Toys first licensed toy product, and maintains a status as one of Japan's most beloved characters. Karza however, was pure evil, and a fitting adversary for Mego's Micronauts line. With his companion steed Andromeda, the two could combine to form a centaur, sharing their power. This was a feat that Mantlo and Golden made tremendous use of in the Marvel Comics. The Marvel Comics version of Baron Karza was created by Bill Mantlo and Michael Golden and first appeared in Micronauts #1. After Marvel Comics lost their license to produce further Micronauts comics, Image Comics re-imagined the Micronauts with their own series which featured a slightly altered, but no less evil version of Baron Karza.
Marvel's version of Baron Karza was pure evil. Mantlo and Golden kept true to Mego's toy design, but the back story and depth of character they added to Karza should not be overlooked or understated. Mantlo created a classic villian with the Baron, a man who is evil to the core, accepts what he is and revels in it. Golden, for his part stayed true to the toy design and gave every piece of Karza's armor a function, including his ability to combine into a centaur form with his horse. Between these two creators they incorporated nearly every toy from Mego's line into their storylines in a logical and natural way that serviced the story rather than hampered it. The concept of interchangeability which was the core conceit of both the Japanese Microman and the American Micronauts toy lines was reworked into the Body Banks idea that persisted throughout the series.