Shaymin, the Gratitude Pokémon. When the Gracidea flower is in bloom, its pollen allows Shaymin to change into its Sky Forme from its Land Forme. Shaymin also have a tendency to migrate.
– Dawn’s Pokedex
Shaymin is one of the many event legendaries in Gen IV. It’s the star of the 11th movie. Land Forme Shaymin is one of the smallest Pokemon, being only 0’08″/0.2m tall; it doubles in height when it changes to Sky Forme. I guess those horn-like things next to its head are its wings in the Sky Forme, though from the anime, it doesn’t flap them when flying, rather Shaymin flies by sort of floating.
Despite being classified as “legendary” and being in the “undiscovered” group (thus it cannot breed), in the movie, there were multiple Shaymin seen. And despite being genderless, I find the Land Forme to look more feminine while the Sky Forme looks more masculine.
I don’t really like Shaymin personally, probably because of the Shaymin from the movie, haha. It acts like a big jerk, and it was kind of annoying. I guess I’m also annoyed by the fact that it’s a pretty exclusive event Pokemon; it was only distributed once near where I live, and I missed it by like 2 years, so I’ve never had a Shaymin.
Stat-wise, its Land Forme has 100 base in every stat, so you can pretty much make it what you want to make it. The Sky Forme has better Speed and Attack and Sp Attack, at a cost to its Defenses. I’m not sure if the additional Flying type in the Sky Forme has much advantage over its pure Grass type in Land Forme though. Grass/Flying isn’t the greatest type combination, as it’s still weak to 5 types, including a double weakness to Ice. It’s immune to Ground, but Grass already resists Ground. Shaymin is one of the few Pokemon to change abilities when it changes Forme. Land Forme Shaymin has Natural Cure, while Sky Forme has Serene Grace. Both are useful abilities, and I can’t really say which is better, I guess it depends on the situation; Natural Cure is more useful defensively while Serene Grace is more useful offensively.