I'm not as far along as I'd like, sadly:

As you can see, enemies can hit you and kill you, but you can't hit them back. I was halfway through programming the collision logic for that when the migraine I've been nursing since Thursday decided to kick in again, so I'm going to call it a night and get some rest and hope I feel better tomorrow. If not, I might just have to call the whole thing off. I'm out of pain relief, I have a bunch of other stuff to do, and I'm not destroying myself for the sake of a game jam.