Two "Heaps" first appeared in The Muppet Show: Sex and Violence sketch Aggression. The two hostile creatures are described in the original script as "gross clumps of crud - fabric, feathers, and foam," and inflict pain on each other and an unimposing stalk. The Purple Heap pummels others with a club, while the Green Heap punches with his fist. The script also notes that they speak in unintelligible guttural sounds.
The two heaps made further appearances on The Muppet Show, only occasionally seen together. In one notable appearance, the Green Heap is seen on the Planet Koozebane in Episode 415, although it's unclear whether or not he was supposed to represent a species indigenous to the planet. Unusually, he is interchanged with the Purple Heap in a backstage scene later in the episode.
- The Muppet Show: Sex and Violence
- The Muppet Show