Jigglypuff
Jigglypuff was introduced in Pokémon Red and Blue, the first Pokémon games. It has appeared in most of the games since then. It evolves into Wigglytuff, an "upgraded" form of Jigglypuff. Starting with Pokémon Gold and Silver, Jigglypuff has a pre-evolved evolutionary form, Igglybuff. Igglybuff was one of the 100 new Pokémon introduced in Gold and Silver. Previously there were only 151.