Shaymin

Shaymin is a Mythical Grass Pokémon introduced in Generation IV. While Shaymin is not known to evolve into or from another Pokémon, it does have a second Forme that can be activated during the day by using a Gracidea flower. Its original Forme, Land Forme, will then transform into the Grass/Flying Sky Forme. During the night or when frozen, Shaymin's Sky Forme will revert to and remain in its Land Forme. Other factors may also cause it to revert.

Shaymin is a white hedgehog-like Pokémon that is small. It has green grass-like fur on its back and a pink flower with two leaves on each side of its head that resembles the Gracidea flower in Land Forme. When it is comfortable, several Gracidea-like flowers appear on its back, but when it detects an impending danger, it quickly hides its back. It has short legs and a plump underside. It has the slender, canine appearance of a small reindeer in Sky Forme. Its back fur grows into a mohawk, and a red flower petal on the left side of its neck resembles a scarf or cape. If Shaymin comes into contact with a Gracidea, it will transform into Sky Forme and then back. It reverts to Land Forme at night or if it is frozen. Shaymin can instantly purify any polluted area of all impurities in the air and transform it into a lush field of flowers. It takes in the polluted air, purifies it inside its body, breaks it down into water and light, and releases the purified substance in a violent, explosive burst.