Rattata

Rattata (コラッタ Koratta) is a small, but unspecified rodent. It is a -type Pokémon. Its most notable feature is its large teeth. Like most rodents, their teeth grow continuously throughout its life, and must be constantly worn down by gnawing. It will bite anything when it attacks, though it will live peacefully side by side with Pidgey.

It evolves into Raticate starting at level 20.

Appearance
Rattata is mouse-like, with large incisors and a whisker on either side. Female Rattata have shorter whiskers than the males. The fur is purple, with a white or cream colored underside. Rattata have red eyes, with no obvious pupils. The tail is long, and curled slightly at the tip. Rattata have three-toed paws, which are the same color as its underbelly.

Special Abilities
Rattata's teeth grow very quickly and they can survive almost anywhere. They also utilize their teeth so they can use attacks such as Super Fang and Bite.

In Anime
A Rattata was seen by Ash Ketchum in Pokémon - I Choose You!, being the second Wild Pokémon he ever saw.

A.J. had three Rattata at his gym in The Path to the Pokémon League.

In Gonna Rule the School, a student used a Rattata in battle.

Many Rattata ran away from the chaos caused by Pokémon Hunter J in Pokémon Ranger and the Kidnapped Riolu! Part One.

Casey had a Rattata in The Double Trouble Header, but it was never seen afterwards.

In Arceus and the Jewel of Life, Rattata appeared in the fight against Marcus.

Origins
Rattata is based off of a rat. Rattata's name incorporates the words rat and possibly attack, considering its original name was going to be Rattatak. Koratta, the Japanese name, comes from rat and the prefix 小 ko, meaning small.

Trivia

 * Rattata was officially have a k at the end of its name, but was removed.
 * If it were to have the k, its name would be Rattatak, and sound like "Rat Attack"
 * Rattata is the first pure -type in the National Pokédex order.
 * Rattata, Pikachu, Raichu, Sandshrew and Sandslash are all known as the Mouse Pokémon.
 * Despite that, Rattata appears to be based off a rat more than a mouse.