Wow! Probably one of the best games I have played from all the submissions so far!
It worked really well, the upgrades were cool and the art was great. The game was kind of difficult, but it is always hard to balance a game in such a short amount of time. The highscore feature is really nice, I wonder what your highscore was.

Love the sound design, although personally for my game preference I find it it a bit slow yet hard which I find very unsatisfying and kinda kills the games mood (which might be just me so ignore this). With a bit more game juice it would be a killer game (bigger bullets, screen shake, etc...) as repetitive games like this one use game juice to satisfy the player, make him feel powerful and keep the player hooked (granted game juice is hard to do in a game jam but noted just as a fyi).  All this aside, for a game jam game, very nice!

Great game ! The variations in the enemies are great and add a lot of depth to the game .The upgrades are great but the accuracy doesn't seem to increase in my eyes XD. It was very nicely executed however it is just a bit difficult for me.