Plagiarized Demons Souls music. Seriously? I'm guessing most things are too. No volume/any settings. No controls tutorial. Pressing fire should autofire instead of needing to spam cluck. For some enemies like the chargers it's hard to tell if you're dealing damage. The progression is really unclear and feels aimless. Bumping you head into ceilings makes you drop straight down, which is bad for platforming. I know it's a staple for Metroidvanias, but the enemies respawning when you leave the screen is annoying. They should at least drop health/items to compensate.
Overall the presentation is excellent, but it's not very interesting. It needs something besides the graphics to stand out.