The game give me this old school retro vibe which I really like, this is also a great concept to build upon and I would love to see a full fledged game.
Starting/Retrying took a while to load for me for some reason, and the numbers above the enemies (I'm guessing how many hits it takes to kill them) are working fine for all enemies except for the skeletons, which always show 30 and never get reduced or changed.
Looks nice and plays well!