I think most people are annoyed with challange 4. An easy key to victory is to have your shield follow your sword and learn how to turn around the dragon so that your shield is always close. Thats how I manage to do it.
I don't see why people argue about the robot controls. I never have trouble with them. Yeah, its loose but really its not hard to win with 2 or three good placements on where they should go.
Do you have to juggle to get the last badge? I can't seem to get over the 70's before I'm overrun. I usually build a long maze and upgrade a lot of squirt towers and bash towers but I still lose.
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