Everybody's dead, Dave :(
The pixel art and music are great. Overall polish is insane! I think that it would have been more fun if it ramped a lot more quickly as there wasn't much challenge until about wave 15, and even at that point, I was able to get hammered until wave 30 before I died. I had fun with it though. Great description as well! A little balancing is all that's really needed for this (and maybe a few more upgrades since you stop upgrading at wave 5). I had a lot of fun with this. Great job!