Mew (Japanese: ミュウ Mew) is a Psychic-type legendary Pokémon. It is not known to evolve into or from any other Pokémon. Mew is notable for its unique ability to learn every Technical Machine, Hidden Machine, and Move Tutor move (except those exclusive to a particular Pokémon or group of Pokémon, such as Draco Meteor and Secret Sword). Mew is the last Pokémon in the Kanto Pokédex. It is a member of the Mew duo along with Mewtwo.
Mew is in Cerulean Cave with Mewtwo. It will ask the player by means of telepathy to help recover Mewtwonite Y because it thinks Professor Oak can upgrade it to Mewnite Y, so that it can become Mega Mew Y. In return, Mew will help battle Fuse.
Mew is one of the few characters whom the player can choose to help in the final fight against Fuse.