This was very cool and different! I got an error at the end - connection error- and I couldn't see any deck cards and there was a chain breaking picture.
Couple of suggestions- at the first or second screen, you spelled developed wrong with two p's, I feel horrible pointing these out but I make so many spelling errors and can never catch them if no one shows me. The player and the enemy look great, but the background is a bit too blurry. Also the story part and the powers are all very cool but the font is too hard to read (even though it fits the horror theme perfectly)
As EsbenNyboe said, sound effects could be cool- though you are right about no sound effects not fitting the empty feel of the game, so maybe they would sound off. I love the audio btw, so spooky, but it loops a lot, I see you composed it yourself (wow, well done :D ) maybe add a second similar track that interchanges since you have the ability to do so? :)