Pichu is the pre-evolved form of Pikachu. It is a small yellow electric mouse, but does not have as much power as a Pikachu. It evolves to Pikachu when it is very happy. There are special forms of Pichu: a notched-ear Pichu, and a Pikachu-colored Pichu as event Pokémon in the "Pokémon HeartGold and SoulSilver" games. Pichu has appeared as an unlockable character in "Super Smash Bros. Melee" where it has a cloned moveset to Pikachu's but takes damage when it uses electric attacks. Pichu features in the intro of the third Pokémon movie.