Managed to get to day 7 (2 times) but that day just killed me. Tried it with different tactics tho. It would be nice if I get an idea for the upgrades, because I don't know how good a point in range or damage is. you should add some information there. Also showing how much each upgrade costs would be good.
The sound and graphics are ok. Your enemies could need some more variation instead of just read eyes or showing the brain. Different colors and visual representation would be good.
I really liked the intro with the text message :D This really transported the theme to the player, but the scene where the citizen got killed is a little confusing to me.
Maybe I give your game a second try later because it would just be fair to really play it till the end.
However, I heard that you repay the favor and you would also play and rate my game. So here is the link. I hope you enjoy it.