What level do they evolve at?
To evolve Seadra you must trade it while it is holding a dragon scale. To get Growlithe to evolve, use a fire stone on it. Neither of them level up through evolving.
Just see this http://pokemondb.net/evolution
Seadra Evolves Into Kingra if You Trade Him Holding The Kings Rock. Growlithe Evolves into Arcanine, if you use a fire stone.
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