Ditto

Ditto is a normal type pokémon and it is the clone of Mew. It's only move is transform which is a move that transforms into the pokémon it sees and learns it's moves. If a ditto was memorizing a pokémon in it's mind it usually gets things wrong. A ditto looks like a pink blob with two eyes and a smiley mouth. It was a failure of cloning Mew. Ditto isn't a legendary or a mythical it's just rare because it's not that perfect for battling.