you get cards by and units buy winning battles and exp is for your hero .. the exp will increase his mana which alows you to use more cards and better cards
awesome game loved the 1st one and love this one NEEDS badges...and all of those complaining about load time the game looks amazing so it will take time an if you still don't like it get better internet connection :P
5/5
and i don't give that score out often
 "Necronator"){kind=icon}
 "Constellations"){kind=icon}
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Which questions in particular? Cause, we did some studying too.