The Creature King first appeared in an episode of Space Ghost called "Creature King." He is able to control animals with the help of the special helmet that he wears.
Backstory: Although Creature King's origins are still very clouded, his origins are most likely linked to gene splicing. The Creature King is not just known for his animal control, he is also very skilled at gene manipulation. This could clear up some things about his shrouded past. If you pay attention to the way Creature King looks you will find he has bat-like fangs and reptilian eyes, and if you look closely at the way his helmet works you will see that it emits a sonar-like beam, very similar to that of a bat. The Creature King might have spliced his DNA with that of a bat and other animals to amplify his mind control abilities. The helmet might not even be the source of his powers, it could just be a way of controlling his powers' strength and frequency.
The Council of Doom: The Creature King was on a team of Super-Villains with the goal of destroying Space Ghost. The other members were: Black Widow (also known as Spider Woman) Metallus, Moltar, Zorak and Brak.
He is the only member who does not appear in Space Ghost Coast to Coast outside of a French dub clip used in the episode "Jacksonville". It was explained in a promotional flyer for the episode "Boatshow" that he left the Council of Doom to run an AV store.