This is a great game. It's really addicting and has brilliant art, but I think it's a little too hard. I've already bought over half of upgrades and barely can make it to the second mini boss, not mentioning beating it. I think the problem lies in lots of things happening on the screen, drawing attention from hostile projectiles. Player can barely distinguish them from other particles, enemies and drops.
My suggestions:
-make the hearts appear more often.
-make the hit boxes a bit smaller.
-make dead enemies less distracting, making them transparrent maybe.
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