Why do only the games with good music offer to mute the soundtrack?
That's a pretty interesting core mechanic, and the twist added with flying enemies was pretty neat. Also, the whole game is very well presented. Shame you didn't have time to make more levels.
I must admit, it took me until the room where you spawn on the morning star to realize only the spike ball actually hurts you. I was making things much harder on myself by dodging the chain too.
I think you could base a full game off these mechanics. It would certainly be neat to see what new mechanics you would come up with to make every level a unique challenge.