A tip to new players and for getting the hard badge: holding mouseclick blocks with the shield. This is very important for fighting ranged enemies and minibosses. I also recommend you pay attention to boss patterns, if you know the pattern you can block all their shots and take little to no damage. With these tips I was able to get to level 10 on my first run, and when I first started this game I'd be lucky to even get to level 4! Hope this helps anyone struggling!
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