A vivarium creature is a type of animal that is kept in an enclosed environment such as an aquarium, terrarium, or other artificial habitat. The most common type of vivarium creature is the NEWT, which is a small amphibian with four letters in its name. Newts are typically found in ponds and streams, but can also be kept in captivity in a vivarium. They are usually carnivorous and feed on insects, worms, and other small invertebrates.