The upgrade mechanic is very interesting and creative! I love being able to change up the modules and alter the gameplay.
Graphically, I think something higher-res would be needed, especially in the text. The anti-aliasing makes some of the words very difficult to read, and there were times I skipped picking modules because it wasn't clear what the description said.
I really liked how the physics of the player and the enemies worked. The projectile gradually gaining speed instead of being at a constant one was a great touch. Also, the visual indicator for enemies spawning was really great for planning out movements. I'm looking forward to more!
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