A color-crawler was a small creature that exuded a colored slime as it slid. Color-crawlers were sold for use in many cosmetic applications and came in a variety of colors, including black, silver, and various shades of brown and green. They were sold in packages sorted by color and were stored in their container until use. Once removed from the pack, crawlers could be applied to an individual's hair or fur or to cloth. They would then move around the surface that they were set on, dyeing it as they went. If several different colors of crawlers were used together it resulted in streaking.