Gameplay: Interesting idea but there are a few problems. One thing I didn't like is running out of ammo can be annoying especially when all of the small bugs are dead. Another thing is the at the beginning of some levels you get immediately damaged by the small bugs.
Graphics: Pixel art looks good but the contrast from the light and dark is a little drastic.
Audio: Sounds are pretty good but there's something about the song that kinda hurts my ears.
Theme interpretation: Doesn't really do anything special with the theme but it fits.
Innovation: Pretty basic shooter though the squishing smaller bugs is nice.
Overall: Nice game. It gets pretty hard by level 5 is there an ending?