The Legendary Birds

The Legendary Birds (also known as Articuno, Zapdos and Moltres) are Legendary Pokemon introduced in Generation I. All three of them are immune to Ground types since they are all Flying.

In Pokémon X and Y, the player can meet one of the birds depending on the starter you chose. If you chose Chespin, then you will meet Articuno. If you chose Froakie, then you will meet Moltres. If you choose Fennekin, then you will meet Zapdos.