Nice game. It took me a while to figure out what the buttons did on the ritual, the incantation, etc... I think a simple puzzle to start that has a bit of a tutorial (or something) on how the switches work would've been nice. I almost gave up but then hit the button and saw it changed. I originally thought I had to deal the cards into the slots in a specific order, I didn't even know I could change them!
Once I got it though. Really cool game. I liked the puzzle idea. It did make me think what other requests the creature behind the door could make? Is there a way to make more levels?
Nice work though. And I loved the atmosphere.
D