Burmy is an interesting new Bug-type pokémon which was introduced in Diamond and Pearl. It can evolve into 4 different forms, making it kinda like Eevee, but not. Just... not.
Each evolution adds a new type -- making it part Bug, part something-else -- and each form learns different moves. Also, the stats are distributed differently for each evolution, though the total remains the same (424)
A male Burmy will evolve into Mothim at level 20.
A female Burmy will evolve into one of three forms of Wormadam at level 20.
Burmy changes its form to match its environment after every battle it participates in. Which form burmy is in when it evolves determines which form the Wormadam will be.
There are three forms:
Wormadam will be part Bug-type, and one of Grass/Ground/Steel as listed above. Mothim is Bug/Flying.
The steel form is the trickiest to get if you've beaten the game — most of the inside battles you fight are with gym leaders and team galactic members, which are one-time battles.
There are, however, a few places where you can repeatedly battle indoors:
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|29||Razor Leaf||Rock Blast||Mirror Shot||Gust|