In exchange for my life

You play as a nameless mage who has made a deal with the devil by exchanging his life for power. You must use your newfound powers to traverse the dungeon (Except it only has one floor). The theme this time was - Your life is currency. My interpretation was that nothing in the game was free and you needed to sacrifice a bit of your health for everything. To cast a spell, you need to wager a portion of your health bar. Get hit and the devil will take that portion away. Moreover, every passive abi...