The Pits

From WikiBrite: The Rainbow Brite WIki

Murky and Lurky live on a grey and gloomy hill above Rainbow Land called The Pits! Threatening smoke always looms above it and inside it's even worse! It's dark and eerie and Murky's laboratory is there. Inside his laboratory, Murky makes concoctions which gurgle and bubble menacingly as he tries to think up more ways to capture Rainbow and the Color Kids. The empty cages are just waiting to be filled!