I like it! It's so neat how you could make it procedurally generated.
I did get these 2 bugs: one time I was about to enter a new room and it did appear, but the door vanished for some reason and I couldn't get in; the other time a new room somehow appeared somewhat overlayed on top of another, and the collisions from both were still working so it was really weird.
Also, I admit that I took some time to realize I could shoot fireballs (though I was managing to survive without it). Once I did, I thought the enemies were a bit tanky and I wasn't sure my shots were doing anything at first.
Other than that, I liked the concept and the presentation is really nice. Good job!