Very impressive for a 5 day jam! I am not very good at binding of Isaac but I've managed to get all the way to the end of this one and quite enjoyed it :) I'd suggest a balance update. By the level two I seemed to have been already unstoppable. Did not have any need for coins anymore so I didn't bother to go through all the rooms after that. At first I didn't know how to open the shop. I kept pressing 'E' but that just restarted the dialogue. As a result, my boss fight took about 5 seconds.