Great submission! I really liked that the combat was very responsive and your particle effects for the enemies' death was really nice. I agree with the other commenter that an indicator until the boss fight would be nice. Or maybe a wave count.
I think I may have came across a bug as well. I got to a point where no new waves loaded in. Maybe that was when the boss was supposed to come in but didn't? Either way, great work, man! Congrats on finishing the jam!