The Mooninites are thieves and con artists that first appeared in Aqua Teen Hunger Forces. The remain completely neutral in the series. They both have big egos, constantly saying how Mooninites are smarter then Humans, and flipping people off.
Ignignokt is the Green one, he is also the obvious leader. He views Earthlings as retards who are inferior to Mooninites. His favorite thing to steal is pornography.
Err is the purple one, who usually repeats Ignignokt. It's unknown if he actually thinksk Earthlings are retards or not, because he tends blindly follow Ignignokt.