I think that he or she evolves at level 30 to Dragonair and 55 to Dragonite.
level 30
the other answers are lies drantini evolves at level 50
you cant
Dratini can be found in Dragonspiral Tower.
well for national dex its dratini and for just black and white pokedex its tornadus you can only get it in black. its like thunderus in white it roams around and it is really hard to find
Weavile does not evolve in Pokemon Black.
All the starters evolve in Pokemon Black. Many other Pokemon evolve as well.
dratini and palkia are the only water-dragon pokemon
You have to fish in Dragonspiral Tower
In the lake of dragon spiral tower
Audino doesnt evolve in Pokemon black and white
Throh don't evolve in Pokemon Black and White.