You people did an amazing job at balancing this game. I was first critical of the large cost increases, but, once I found out that there are limits, it felt great. I was never really sure if a wave would make it through and it took some careful planning to get to a point where I felt ahead.
The mechanic, where nightmares that make it through destroy tiles, is cool. It does however make the game harder and harder as you struggle more and more, which is unforgiving and makes the early game depend on some good rng. (I haven't yet managed to reach the lategame without some nightmares going through. Every attempt I had to hope for none of my towers to get destroyed.)
Some way to upgrade corrupted tiles back into their regular ones could be interesting. Maybe even allow people to invest a small amount to restore towers that were corrupted.
Some more data on the towers would also be greatly appreciated. It would make the crucial early game decision making a bit easier. It took me a ton of tries to even get to a point where I felt like I knew what I was doing.
I really like everything that I haven't criticised. The fun art, chill music, theme interpretation and their fantastic combination all set a perfect mood and make this game overall feel very consistent.
I'm stunned by the sfx. I imagined them to layer into hell, but somehow you managed to make them sound nice for any stack size. Please explain how that magic works!