Demolition Crew is the group of people that demolishes buildings. For demolishing houses they use claw shovels and for demolishing tall buildings they use wrecking balls (currently spherical and formerly pear-shaped with a portion of the top cut off). The Demolition Crew first appeared in the episode of Corduroy "Flight of Fancy" in Corduroy's imagination on his kite building a new building. And The second appearance is them destroying the South Park Studios with a big round spherical wrecking ball and letting a McDonald's with a big huge indoor PlayPlace take over the South Park Studios.
Flight of Fancy