Move constantly, only stand on flags or when about to get hit, upgrade your Power to max first, then Rate of Fire on ~10, then start investing in speed/rate of fire and voila - hard badge.
Another trick is to stand on leftmost flag zone when enemies spawn - this way if you retreat to your right and then up, enemies will line up in a single line and you can kite them around the books without getting hit. Hope that helps.
This idea behind the game is awesome, however, balance is really off. Either i'm very unlucky with random numbers or i just suck, but i'm getting overwhelmed by level ~11-12. I tried different classes and different strategies, but the game seems to be too hard even on casual mode...
the strategy is very simple.
buy as many cheapest things you can and use it wisely.
good shot and 3 thrusters right after the shot and then skis and fish in right times will do th >7000 score. good luck!
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