Simply put, it doesn't. You are probably referring to shaymin's form change. You can change it's form by showing the lady in the flower shop in goldenrod city (there's a lady standing out side in Floroma town in platinum) the shaymin from a 2009 event.
Sorry, but Shaymin Doesn't evolve. It only has a different form, which is accessed by Gracedia flowers, or something like that. You give shaymin the flowers (in day) and it turns to sky forme.
Shamin does NOT evolve.
shaymin does not evolve
bagon will just evolve into shelgon
psyduck evolves into golduck at level 33
Wingull evolves at level 25 into pelipper
it matters on their happiness, when they are happy enough you level them up and they evolve its also good to use a friend ball when catching it
sadly......no it's level will be to high to get it higher
45 and so does shaymin
shaymin can not evolve
Shaymin cannot evolve.
Although Shaymin doesn't evolve, it does have two different forms.
Shaymin does not evolve in Pokemon Diamond.
you cant. shaymin is like, legendary.
The land Shaymin. Your choice is to make it land or Sky. But it doesn't technically evolve. It transforms into a Sky Shaymin.
There is no evolution. But you can change its form into a skaymin. (Sky Shaymin)
Shaymin doesn't evolve, but you can change it's form by using the Gracedia flower, which can be given to you by a girl in Floraroma Town if you have a Shaymin in your party.
no but it has a sky form
Shaymin dosent evolve. But to chnge the forme go to Floaroma Town flower shop and get the flower use it on shaymin and wham! PS have shaymin as first in your party
It doesn't evolve, but it changes forms with the help of a Gracidea Flower.