The unlucky wave concept took me a few runs to fully understand, but it is a cool addition to this kind of shooter. Interesting to get cards like one that adds to all stats when unlucky, and in general it felt like there was some fun variety with builds.
I like the use of the shifting colors with each level too, I think that along with the well paced/consistent sounding music really helps to give some drive forward and a desire to see the whole thing.