In Pokemon White, Iris is the 8th and final Gym Leader in the Unova Region. She runs the Opelucid City Gym. If you defeat her she gives you the Legend Badge and TM 82 Dragon Tail. Iris makes a few notable appearances throughout the game, trying to help the player stop Team Plasma and also helping Bianca retrieve her stolen Pokémon early on.
Iris also plays a big role in the Anime. Not much is known about Iris before she meets Ash, but she decides to join him as a traveling companion early in the Best Wishes series, set in the Unova region.
In The Anime
Iris, native to Unova, acts as a guide for Ash and Pikachu when they first decide to embark on their journey there. Unlike many of Ash's previous traveling companions, Iris likes to rough it while traveling; she can frequently be seen climbing and swinging through trees. Similar to Ash's Pikachu never staying in its Pokéball, Iris' Axew likes to stay in her hair. Her catchphrase, "What a kid" Is usally directed toward Ash .