Ugly Goo is a species of Goo in the video game World of Goo. They are first introduced in the level Volcanic Percolator Day Spa, and have the extra ability to be broken down into 18 Small Ugly Goo that are often used for their durability. The Ugly Goo has a sister Goo named Beauty Goo which in contrast is pink in color and supposedly much prettier than the Ugly Goos, which, the game implies heavily, should be used for sacrificial acts to help Beauty Goo, as referenced in Genetic Sorting Machine.