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Rattata is a small, quadruped rodent Pokémon. Its most notable feature is its large teeth. Like most rodents, its teeth grow continuously throughout its life and must be worn down by gnawing. It has long whiskers and a long, slightly curled tail. Rattata has purple fur on its back, and cream fur on its stomach. Females have shorter whiskers and lighter fur color.
Rattata can live wherever it can find food, which it searches for most of the day. Thanks to its sharp fangs, it is able to eat nearly anything. Its hardiness lets it live in many environments, although it mainly lives on plains and savannas. Because it reproduces so quickly, a pair of Rattata can quickly colonize an area. When it is threatened, Rattata can deliver a powerful bite.