It has a nice retro feel. It would help if you list out all the controls on the description. I figured out arrows to move and it looks like Q to attack. I tried clicking the other buttons too but got a bit frustrated not knowing what I'm doing.
Thanks a lot for the feedback! I'm aware of this — right now I'm focusing more on tuning the core game mechanics than on the controls UX, but it's definitely on my plan. Later I want to add a simple tutorial in the first room, plus an in-game encyclopedia describing all the game objects, so players won't have to figure everything out by trial and error.