Game is now free, I forgot to make it free earlier.
Okay, I just played through once. I got to floor 13 before dying. I really like this game. You've done a wonderful job. I like how simple it is, and the music is catchy.
Pros: simple, cute graphics; good music; easy gameplay
Cons: I think you should lock it into landscape view (on my Android phone, it flips between portrait/landscape); when I was killed, my HP went to negative numbers
Ideas: what about showing enemy HP (maybe by enemy's head), show your player's current experience or experience needed for level up.