This was surprisingly fun! We got the hammer and did our best to group up the mobs together and then unleash massive damage. I think some variety in music would have been interesting, as well as some sense of progress: are the waves unending? Do they get harder?
The implementation with the loop theme was also good: it made for some good strategies as you tried to go back and forward to either group mobs or isolate them, depending on what weapon you had.