After reading through the comments, I know that a lot of people complain about the medium badge, and sure, it might be a bit tough. But hey, the game's all about progression through thought and strategy. I play TCGs a lot and didn't find the medium badge all that tough, but that's because I already had experience in the field. The game isn't all that newbie friendly, and while this could be improved upon, there's an awesome community here to answer questions and give advice. My suggestion is, if you're new, utilize it, it's here for you. :)
I really feel as though the price for PVP1 should be corrected. It's actually 30, yet it says 20. Can't tell you how many times I've forgotten it's off and been gotten the not enough electrum sign. xD
I agree that grinding for the upgrades is a tad annoying, and that the upgrades are a bit too expensive. The game is great overall, besides that... 4/5.
Nexus Campaign badge: Definitely an endurance badge. And it's somewhat tough otherwise. My hints are to find a deck that's easy to run and follows a certain trend (IE Rally or Strike), and improve as you go along. Oh, and don't forget: Defense is just as important as offense.
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