It really needs the music and sounds, it would make a huge difference (just find some 8-bit sounds and songs on the yt library and it will do the trick)...
Anyway, this is probably one of the best ideas I came across so far. If the bullets you shot would bounce for a little big longer, it would maybe get more exciting and challenging.
I also like the simple look of it, but at the same time having the bullets fly across with motion blur.
I am also happy it worked in browser so well without any lag.
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