Moo-ing the Merciless is the evil emperor of Lactosia, and the primary villain in the "Lash Holstein: Space Cowdet" serial, as seen in episode 202 of Muppets Tonight.

In the sketch, he fights against Lash Holstein over the hand of Dorothy BoVine. He employs a henchman who keeps Lash Holstein busy while Moo-ing tries to escape to the planet Lactosia. His father was Hazel the Well-Accessorized, who passed on his cape.

Moo-ing is a spoof of Ming the Merciless, the villain of the Flash Gordon comic and serials.