Quote originally posted by XanderO:
So. If you use a team of Rock/Grounds, you'll get both the Rock and Ground medals right?
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Yes, that's why if you want to get those medals, it's best to do a solo run.
I beat league with Lucario and got both Fighting and Steel medal. So dual typing works.
Though, like it has been said, Pokemon Black 2 and White 2 are very new Pokemon games, regardless of their release being just a few months ago. Not very many codes have been generated, so the best thing to do now is be patient, and keep checking back at a search engine.