Awesome game. Only had 2 badges left to go back and get when I finished it the first time. Wave 55 is good for getting your kill count up if you're going back after finishing it!
Here's a tip that helped me get the impossible badge, if you have triple shot and collect a double shot power up then it just refills your triple, so use that to keep it going as long as possible.
Hmmm, maybe I got an easy game buy all I did was buy artillary and gold nail then just upgrade whenever I could, didn't even lose any life. Not exactly a "hard" badge...
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