So basically i hit "NaN" frequenzy and damage. I think i got to the maximum number of your used datatype. The tower stops shooting after that.
I think you did a very good job to implement the jam's theme. I am always glad to see that tower defense games made it into the jam.
I love the overall gameplay and the concept of making your towers stronger by placing structures around them. They even interact with each other. Very nice!
However, i would have liked more feedback on how objects interact with each other. This would make it much easier to strategically consider which object you want to place.
Overall i think this is a pretty good tower defense game, with a very creative idea. Good job.