Nice entry, I like the idea, I think the bullets are too small, also usually when shooting towards an enemy thats near a button makes me press it (kinda frustating when its the pause)

There are some really cool ideas here! The different toweres that the enemies want to destroy having different functions that change how the game controls is a really cool approach to the theme. 

I did have some issues however. The game was far too zoomed out and learning what each tower did and how to play the game was hard because the enemies were already incoming when the text showed up.