Solid premise and it delivers. Chaotic game but I see the charm in it, it has a lot of potential.
What I liked:
1. Soundtrack
2. The nun's hysterical laugh when she goes into a frenzy
3. The fact that gravity shifts when you go from surface to surface
What I didn't like:
1. That you can't absorb shield/health if you touch it, only by shooting it you get it.
2. Stuff can get too chaotic sometimes and you end up going in circles shooting everywhere.
3. Some places between gravity shifts (like near the heart spawn point) are a bit fucky and you might not be able to jump comfortably from 1 side to the other.
Suggestions:
1. Need timer or visual feedback for the hallelujah bomb cooldown/recharge. Also for when you somehow start getting shields from killing demons.
2. Need other feedback (visual or audio) that you're being damaged aside from the red blinking. The whole scenario is red so it doesn't stand out.